JP2014092254A - Power transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission capable of suitably transmitting and receiving power between first and second wheels as well as allowing miniaturization of the whole device, thereby improving the driving performance of a vehicle.SOLUTION: A power transmission 1 includes: first to third rotation elements S1, C1 and R1 constituted so that their rotation speeds satisfy a collinear relation with each other; fourth to sixth rotation elements S2, C2 and R2 constituted so that their rotation speeds satisfy a collinear relation with each other; first and second brake means 7 and 9 for respectively braking the third and the sixth rotation elements R1 and R2; a first disconnection and connection means 8 for connecting and disconnecting between the first rotation element S1 and the third rotation element R1; and a second disconnection and connection means 10 for connecting and disconnecting between the fourth rotation element S2 and the sixth rotation element R2. The frist and the fourth rotation elements S1 and S2 are connected so as to be integrally rotatable. The second rotation element C1 is connected to a first wheel WRL, and the fifth rotation element C2 is connected to a second wheel WRR.

Description

  The present invention relates to a power transmission device capable of transmitting power between a first wheel and a second wheel of a vehicle.

  Conventionally, as this type of power transmission device, for example, the one disclosed in Patent Document 1 is known. This power transmission device is applied to a snow vehicle and includes a left planetary gear device and a right planetary gear device. Both the left and right planetary gear units are of a single pinion type, and their left and right sun gears are connected to each other so as to be rotatable together (directly connected) and are connected to an engine that is a power source of the snow vehicle. ing. Further, the left and right ring gears of the left and right planetary gear devices are connected to left and right Caterpillar (registered trademark), respectively.

  The left planetary gear unit further includes first and second left brakes that can brake the left carrier and the left ring gear, respectively, and a left clutch that can connect / disconnect between the left carrier and the left ring gear of the left planetary gear unit. Is provided. Similarly, the right planetary gear device includes first and second right brakes that can brake the right carrier and the right ring gear, respectively, and a right clutch that can connect / disconnect between the right carrier and the right ring gear of the right planetary gear device. Is provided.

  In the conventional power transmission device having the above-described configuration, in order to improve the turning performance of the snow vehicle while the engine is being driven, the left clutch, the first and second left brakes, the right clutch, the first and second right brakes, It is controlled as follows. That is, when the snow vehicle turns left, the left clutch and the left ring gear are disconnected by the left clutch, the left carrier braking by the first left brake is released, and the left ring gear is braked by the second left brake. Further, the right carrier and the right ring gear are connected by the right clutch, and the braking of the right carrier and the right ring gear by the first and second right brakes is released.

  As described above, the braking force of the second left brake acts on the left caterpillar. Further, the right sun gear, the right carrier, and the right ring gear rotate as a result of the connection of the right clutch, whereby the driving force of the engine transmitted to the right sun gear is transmitted to the right caterpillar via the right ring gear. In this way, when the snow vehicle turns left, the braking force acts on the left caterpillar and the driving force of the engine is transmitted to the right caterpillar, thereby improving the turning performance of the snow vehicle. Further, when the snow vehicle turns right, the left clutch, the first and second left brakes, the right clutch, and the first and second right brakes operate in the opposite direction to the above. Swivel is improved.

Japanese Utility Model Publication No. 49-132523

  As described above, in the conventional power transmission device, the braking force of the second left brake is directly applied to the left caterpillar in order to improve the turning performance of the snow vehicle, so that the left caterpillar acts on the second left brake. Because the torque to be applied is large, the second left brake must be enlarged. The same applies to the second right brake. Further, since the right carrier and the right ring gear are connected by the right clutch in order to transmit the driving force of the engine, the torque acting on the right clutch increases and the right clutch becomes large. This is true for the left clutch as well. Due to the increase in the size of the second left brake, the second right brake, the right clutch, and the left clutch, the entire power transmission device is increased in size.

  Moreover, in the conventional power transmission device, power cannot be transferred between the left and right caterpillars while the engine is stopped for the following reason. That is, as described above, the left and right caterpillars are connected to the left and right ring gears, respectively, and the left and right sun gears are directly connected to each other. In this configuration, for example, for the left planetary gear device, the left caterpillar torque transmitted to the left ring gear is transmitted to the left sun gear by releasing the braking by the second left brake and braking the left carrier by the first left brake. Sometimes, the torque of the left caterpillar acts to brake the left and right sun gears (to rotate in the direction opposite to the rotation direction of the left ring gear).

  In this state, when the right planetary gear unit is released from braking by the first and second right brakes and is connected between the right carrier and the right ring gear by the right clutch, in addition to the right sun gear, the right ring gear and the right The braking force also acts on the caterpillar. The above operation is similarly applied when various elements are performed with the left and right reversed. As described above, in the conventional power transmission device, while the engine is stopped, the braking force of the first left (right) brake can only be applied to both the left and right caterpillars. Cannot exchange power.

  The present invention has been made in order to solve the above-described problems, and can reduce the size of the entire apparatus and appropriately transfer power between the first and second wheels. Thus, an object of the present invention is to provide a power transmission device that can improve the traveling performance of the vehicle.

  In order to achieve the above object, the invention according to claim 1 is the first wheel and the second wheel of the vehicle V (the left and right rear wheels WRL, WRR in the embodiment (hereinafter the same in this section)). The power transmission devices 1 and 51 capable of transmitting power include a first rotating element (first sun gear S1), a second rotating element (first carrier C1), and a third rotating element (first ring gear R1). The first planetary gear device PS1 configured so that the rotation speeds of the first to third rotating elements satisfy the collinear relationship arranged in this order on a single straight line in the collinear diagram, and a fourth rotating element (first 2 ring gear R2), fifth rotation element (second carrier C2) and sixth rotation element (second ring gear R2), and the rotation speeds of the fourth to sixth rotation elements are on a single straight line in the collinear diagram. The second planetary gear device is configured to satisfy the collinear relationship arranged in this order. PS2, coupled to the third rotating element, coupled to the first rotating means (first brakes 7, 52) for braking the third rotating element by fastening and releasing the brake by releasing, and to the sixth rotating element, The sixth rotating element is braked by fastening, and the second braking means (second brakes 9 and 54) for releasing the braking by releasing and the first and third rotating elements are connected, and the first rotating element is fastened and released. The first connecting / disconnecting means (first clutches 8 and 53) for connecting / disconnecting the third rotating element and the third rotating element, and the fourth and sixth rotating elements are connected to the fourth rotating element and the sixth rotating element by fastening / release. Second connecting / disconnecting means (second clutches 10 and 55) for connecting / disconnecting between the elements, and the first and fourth rotating elements are coupled to each other so as to be integrally rotatable. Is connected to the first wheel and requires a fifth rotation. It is characterized in that it is connected to the second wheel.

  According to this configuration, the rotation speeds of the first to third rotating elements of the first planetary gear device are collinear with each other, arranged in this order on a single straight line in the collinear diagram, and the second planetary gear. The rotation speeds of the fourth to sixth rotating elements of the gear device are collinear with each other, and are arranged in this order on a single straight line in the collinear diagram. The third and sixth rotating elements are braked by the first and second braking means, respectively, and the first rotating element and the third rotating element are connected by the first connecting / disconnecting means by the first connecting / disconnecting means. The six rotating elements are connected / disconnected by the second connecting / disconnecting means. Further, the first and fourth rotating elements are connected to each other so as to be integrally rotatable, the second rotating element is connected to the first wheel, and the fifth rotating element is connected to the second wheel.

  From the above configuration, the rotational speed relationship between the various types of rotary elements in the power transmission device is shown in FIG. 13, for example. In the figure, the second rotating element and the first wheel and the fifth rotating element and the second wheel are directly connected to each other, but may be connected via a gear or the like. Hereinafter, the operation of the power transmission device will be described with reference to FIG.

  For example, when a part of the power of the first wheel is transmitted to the second wheel, the third rotation element is braked by fastening the first braking means, and the first rotation is made by releasing the first connecting / disconnecting means. Block between the element and the third rotating element. As a result, the torque of the first wheel transmitted to the second rotating element is transmitted to the first rotating element using the braking force of the first braking means acting on the third rotating element as a reaction force, and further to the fourth rotating element. Is transmitted to. In FIG. 13, T2 is a torque transmitted from the first wheel to the second rotating element, and B3 is a braking force of the first braking means acting on the third rotating element. R1 is a reaction torque acting on the first rotating element, T4 is a torque transmitted to the fourth rotating element, and the magnitudes of both are equal.

  In addition to the above-described operation, braking of the sixth rotating element is released by releasing the second braking means, and the fourth rotating element and the sixth rotating element are connected by fastening the second connecting / disconnecting means. Thereby, as described above, the torque transmitted from the first wheel to the fourth rotating element via the second and first rotating elements is also transmitted to the sixth rotating element via the second connecting / disconnecting means. As a result, torque obtained by synthesizing torque transmitted to the fourth and sixth rotating elements is transmitted to the second wheel via the fifth rotating element. In FIG. 13, T6 is a torque transmitted to the sixth rotating element, and R5 is a reaction force torque acting on the fifth rotating element from the second wheel.

  As apparent from FIG. 13 and the above operation, the first and second braking means and the first and second connecting / disconnecting means described above make part of the power of the first wheel the first and second planets. It is transmitted to the second wheel via the gear device. In other words, a braking force acts on the first wheel and a driving force acts on the second wheel.

  Contrary to the above, the second braking means is fastened, the second connecting / disconnecting means is released, the first braking means is released, and the first connecting / disconnecting means is fastened, whereby the power of the second wheel is Is transmitted to the first wheel via the second and first planetary gear units. In other words, a braking force acts on the second wheel and a driving force acts on the first wheel. As described above, since power can be appropriately exchanged between the first and second wheels, the power of both can be freely changed, and thus the traveling performance of the vehicle can be improved.

Further, as shown in FIG. 13, the distance between the vertical line representing the rotation speed of the first rotation element and that of the second rotation element in the collinear diagram is α, and the vertical line representing the rotation speed of the second rotation element. Is the distance between the first rotating element and that of the third rotating element, β is the vertical line representing the rotational speed of the fourth rotating element and γ is the distance between it and the fifth rotating element, and the vertical line is the rotational speed of the fifth rotating element. And δ is the distance between the first rotation element and the sixth rotation element. The relationship between the braking force B3 of the first braking means acting on the third rotating element and the torque T2 transmitted from the first wheel to the second rotating element (that is, the braking force acting on the first wheel) is expressed by the following equation ( 1).
B3 = T2 / (1 + α / β) (1)

  As is clear from this equation (1), the first left side (right side) brake force is applied directly to the left (right) caterpillar as in the conventional power transmission device described above. Torque acting on the braking means can be reduced. This means that the first planetary gear unit, the first braking unit and the first connecting / disconnecting unit, and the second planetary gear unit, the second braking unit and the second connecting / disconnecting unit are connected to the first and second wheels. Since it is provided symmetrically to each other, the same applies to the second braking means. As described above, the first and second braking means can be reduced in size.

Furthermore, since the fourth connecting element and the sixth rotating element are connected by the second connecting / disconnecting means, the torque acting on the second connecting / disconnecting means is expressed by the following equation (2).
T4 + T6 = (1 + γ / δ) T4 (2)

On the other hand, as in the conventional case described above, if the fifth rotating element compared to the conventional right carrier and the sixth rotating element compared to the right ring gear are connected by the second connecting / disconnecting means, The torque acting on the second connecting / disconnecting means is expressed by the following equation (3).
R5 + T6 = (1 + 2 × γ / δ) T4 (3)

  As is clear from a comparison between these formulas (2) (present invention) and formula (3) (conventional), the torque acting on the second connecting / disconnecting means can be reduced as compared with the conventional case. The contact means can be downsized. This means that the second planetary gear unit, the second braking unit and the second connecting / disconnecting unit, and the first planetary gear unit, the first braking unit and the first connecting / disconnecting unit are connected to the first and second wheels. Since it is provided symmetrically, the same applies to the first connecting / disconnecting means. By reducing the size of the first and second braking means and the first and second connecting / disconnecting means, the entire power transmission device can be reduced in size.

  In addition, when the vehicle is running, the first and second braking means and the first and second connecting / disconnecting means are released, and as is apparent from FIG. Can be held in.

  The invention according to claim 2 is the power transmission device 1, 51 according to claim 1, further comprising a first prime mover (rotating electrical machine 4) capable of outputting driving force, wherein the first and fourth rotating elements are It is connected to 1 prime mover.

  According to this structure, the 1st prime mover which can output a driving force is connected with the 1st and 4th rotation element. For this reason, by adjusting the braking force of the first braking means or the fastening force of the first connecting / disconnecting means, the driving force (number of revolutions) distributed (transmitted) from the first prime mover to the first wheels is freely changed. The driving force (number of revolutions) distributed from the first prime mover to the second wheel can be freely changed by adjusting the braking force of the second braking means or the fastening force of the second connecting / disconnecting means. Can do. Therefore, the running performance of the vehicle can be further improved.

  According to a third aspect of the present invention, in the power transmission device 1, 51 according to the first or second aspect, the first and second braking means and the first and second connection / disconnection means operate by supplying fluid pressure, A fluid pressure supply device (hydraulic pump 15) is connected to the first and fourth rotating elements and supplies fluid pressure to the first and second braking means and the first and second connecting / disconnecting means. And

  According to this configuration, the first and second braking means and the first and second connection / disconnection means are operated by the supply of fluid pressure from the fluid pressure supply device. In addition, since the fluid pressure supply device is connected to the first and fourth rotating elements, the fluid pressure supply device uses the power of the first and second wheels transmitted to the second and fifth rotating elements, respectively. Can be driven. Further, when the first prime mover is connected to the first and fourth rotating elements as described in claim 2, the fluid pressure supply device can be driven using the driving force of the first prime mover. . Therefore, it is not necessary to provide a separate drive device for driving the fluid pressure supply device, and accordingly, the entire power transmission device can be reduced in size.

  In this case, since the fluid pressure supply device is connected to both the first and fourth rotating elements, the load of the fluid pressure supply device is not applied to only one of the first and second wheels, Therefore, high running stability of the vehicle can be ensured.

  According to a fourth aspect of the present invention, in the power transmission device 1 or 51 according to any one of the first to third aspects, the rotational speed of one of the first and second wheels is higher than the rotational speed of the other wheel. The first and second rotating elements connected to one of the wheels and the first rotating element connected to one of the rotating elements of the third and sixth rotating elements whose rotational speed is collinear. One of the second braking means and the other of the first and second braking means are released, and the first and second rotating elements of the third and sixth rotating elements are in collinear relation with the one rotating element. First control for releasing one of the first and second connecting / disconnecting means connected to one of the first and fourth rotating elements and controlling the other fastening force of the first and second connecting / disconnecting means Further comprising means (ECU 2, steps 3, 4, 6, 7 in FIGS. 4 and 11) And features.

  According to this configuration, when the rotational speed of one of the first and second wheels is made higher than the rotational speed of the other wheel, the following control operation is performed by the first control means. That is, the first and second rotation elements connected to one of the rotation elements of the third and sixth rotation elements whose rotation speed is collinear with one rotation element of the second and fifth rotation elements connected to one wheel. One of the two braking means is fastened and the other of the first and second braking means is released. Further, the first and second rotating elements connected to the one rotating element of the third and sixth rotating elements and the one rotating element of the first and fourth rotating elements that are collinear with the one rotating element. While one of the connection / disconnection means is released, the other fastening force of the first and second connection / disconnection means is controlled. As is apparent from the above control operation and the description of the invention according to claim 1 using FIG. 13, power can be exchanged between the first and second wheels more appropriately.

  Further, as described in the description of the invention according to claim 2, when the first and fourth rotating elements are connected to the first prime mover, the driving forces distributed from the first prime mover to the first and second wheels, respectively. Can be appropriately changed, and therefore the running performance of the vehicle can be further improved.

  According to a fifth aspect of the present invention, in the power transmission device 1, 51 according to any one of the first to fourth aspects, the first and second wheels are rotated when the first and second wheels are rotated at the same rotational speed. It is characterized by further comprising second control means (ECU 2, FIG. 4) for fastening the braking means and releasing the first and second connecting / disconnecting means.

  According to this configuration, when the first and second wheels are rotated at the same rotational speed, the first and second braking means are fastened by the second control means, and the first and second connection / disconnections are also made. Means are released. Thus, in the collinear diagram shown in FIG. 13 described above, for example, when α / β = γ / δ, as is apparent from this collinear diagram, the first and second wheels are rotated at the same rotational speed. Thereby, higher running stability of the vehicle can be ensured.

  Further, as described in the description of the invention according to claim 3, when the first and second braking means are fastened by the supply of fluid pressure from the fluid pressure supply device, the first and second braking in the released state The time required to fasten the means tends to be long and its responsiveness is relatively low.

  On the other hand, according to the present invention, when the first and second wheels are rotated at the same rotational speed as described above, the first and second braking means are held in the engaged state. For this reason, in order to make one of the first and second wheels higher than the other from this state, when power is exchanged between the first and second wheels described in the description of the invention according to claim 1 It is only necessary to stop the supply of fluid pressure to one of the first and second braking means, and it is not necessary to supply the fluid pressure to the other of the first and second braking means from the beginning. Transfer of power between the second wheels can be started early. Similarly, the change of the driving force transmitted from the first prime mover of claim 2 to the first and second wheels can be started at an early stage.

  Further, a hydraulic pump is used as the fluid pressure supply device, and the first and second braking means and the first and second connection / disconnection means are fastened by supplying hydraulic pressure of the hydraulic oil from the fluid pressure supply device. In the case where the hydraulic oil is used as the lubricating oil for the power transmission device, the following effects can be obtained. That is, as described above, whenever the first and second wheels are rotated at the same rotational speed, in order to fasten the first and second braking means, the hydraulic pressure of the hydraulic oil is supplied to both from the fluid pressure supply device. Supplied. Thereby, since the quantity of the hydraulic fluid stored in the power transmission device can be reduced, the stirring resistance of the hydraulic fluid when the first to sixth rotating elements rotate can be suppressed.

  The invention according to claim 6 is the power transmission device 1, 51 according to any one of claims 1 to 5, wherein the first and second wheels are the left and right wheels of the vehicle V (left and right rear wheels WRL, WRR, respectively). In addition to the first and second wheels, the vehicle V includes a third wheel (left and right front wheels WFL, WFR) capable of operating the steering direction, and a first prime mover for driving the third wheel. A second prime mover (engine 3) different from the above is provided.

  According to this configuration, since the first and second wheels are the left and right wheels of the vehicle, respectively, the turning performance of the vehicle is improved by the operations of the first and second braking means and the first and second connecting / disconnecting means described above. Can be improved. Moreover, since the 3rd wheel provided in the vehicle is driven by the 2nd prime mover, and it is comprised so that a steering direction can be changed, the turning property of a vehicle can be improved further.

  The invention according to claim 7 is the power transmission device 1 according to any one of claims 1 to 6, wherein the first and second braking means (first and second brakes 7 and 9) and the first and second disconnections are provided. The contact means (first and second clutches 8 and 10) are characterized in that they are arranged on the inner side in the radial direction with respect to the third and sixth rotating elements.

  According to this configuration, since the first and second braking means and the first and second connecting / disconnecting means are arranged radially inward of the third and sixth rotating elements, the diameter of the entire power transmission device The size of the direction can be reduced.

  The invention according to claim 8 is the power transmission device 1, 51 according to any one of claims 2 to 7, wherein the first prime mover is the rotating electrical machine 4.

  According to this configuration, since the rotating electric machine having higher responsiveness than the internal combustion engine is used as the first prime mover, the responsiveness of driving the first and second wheels by the first prime mover can be enhanced.

  The invention according to claim 9 is the power transmission device 1 according to any one of claims 2 to 8, wherein the first and second planetary gear devices PS1, PS2 are arranged on the same axis line, and the axis line In this direction, the first and second planetary gear devices PS1, PS2 and the first prime mover are arranged so as to overlap each other.

  According to this configuration, the first and second planetary gear devices are arranged on the same axis, and the first and second planetary gear devices and the first prime mover overlap each other in the direction of the axis. Since it arrange | positions so that it may do, the magnitude | size of the radial direction of the whole power transmission device can be made small.

1 is a diagram schematically showing a power transmission device according to the present invention together with a vehicle to which the power transmission device is applied. FIG. It is a skeleton figure which shows the power transmission device by 1st Embodiment. It is a block diagram which shows ECU etc. It is a figure which shows operation | movement of the various elements in the various operation modes of a power transmission device. It is a collinear diagram which shows the relationship of the rotational speed between the various rotation elements in a power transmission device, and the balance relationship of torque about the straight drive assistance mode. It is a figure which shows the transmission condition of the motive power in a power transmission device in the straight drive assist mode. It is a collinear diagram which shows the relationship of the rotation speed between the various rotation elements in a power transmission device, and the balance of torque about the left turn assist mode. It is a figure which shows the transmission condition of the motive power in a power transmission device about the left turn assist mode. It is a collinear diagram which shows the relationship of the rotation speed between the various rotation elements in a power transmission device, and the balance of torque about the high-speed left turn mode. It is a figure which shows the transmission condition of the motive power in a power transmission device in high speed left turn mode. It is a flowchart which shows the process which sets an operation mode at the time of turning of a vehicle. It is a skeleton figure which shows the power transmission device by 2nd Embodiment of this invention. It is a collinear diagram which shows the relationship of the rotation speed between the various rotation elements in the power transmission device of this invention, and the balance of torque.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. A vehicle V shown in FIG. 1 is a four-wheel vehicle including left and right front wheels WFL, WFR and rear wheels WRL, WRR, and an internal combustion engine (hereinafter referred to as an “engine”) 3 as a power source is provided at the front portion thereof. It is installed. The steering direction of the left and right front wheels WFL, WFR is changed by the driver operating a handle (not shown), whereby the traveling vehicle V turns left and right.

  The engine 3 is, for example, a gasoline engine, and its crankshaft 3a is connected to the left and right front wheels WFL and WFR via the clutch CL, the transmission TM, the differential gear DG, and the left and right front shafts SFL and SFR. Has been. The output of the engine 3 is transmitted to the left and right front wheels WFL and WFR via these transmissions TM and the like.

  A power transmission device 1 is mounted on the rear portion of the vehicle V. As shown in FIG. 2, the power transmission device 1 includes first and second planetary gear devices PS <b> 1 and PS <b> 2 arranged coaxially with each other, and a rotating electrical machine 4, and these rotating electrical machines 4, first and second The second planetary gear devices PS1 and PS2 are accommodated in a case CA fixed to the vehicle V. The case CA stores an oil OIL that is a lubricating oil such as the first and second planetary gear devices PS1 and PS2.

  The first planetary gear device PS1 is a single pinion type planetary gear device, and includes a first sun gear S1, a first ring gear R1 provided around the first sun gear S1, and a plurality of (for example, three) first gears meshing with both the S1 and R1. The first pinion gear P1 and the first carrier C1 that rotatably supports the first pinion gear P1 are provided. Similar to the first planetary gear device PS1, the second planetary gear device PS2 is a single pinion type planetary gear device, and includes a second sun gear S2, a second ring gear R2, a plurality of second pinion gears P2, and a second carrier C2. Have.

  As is well known, the first sun gear S1, the first carrier C1, and the first ring gear R1 are configured so that their rotational speeds satisfy a collinear relationship arranged in this order on a single straight line in the collinear diagram. This also applies to the second sun gear S2, the second carrier C2, and the second ring gear R2. The number of teeth of the first sun gear S1 and the number of teeth of the second sun gear S2 are set to the same value, and the number of teeth of the first ring gear R1 and the number of teeth of the second ring gear R2 are set to the same value.

  The first and second sun gears S1 and S2 are connected to each other via a connecting shaft 5 and are rotatable together. A gear 6 is coaxially and integrally provided on the connecting shaft 5, and the gear 6 is disposed at the center in the left-right direction of the connecting shaft 5. The first carrier C1 is connected to the left rear wheel WRL via the left rear shaft SRL, and the second carrier C2 is connected to the right rear wheel WRR via the right rear shaft SRR. Each of the left and right rear shafts SRL and SRR is rotatably supported by the case CA, and is rotatable integrally with the first and second carriers C1 and C2.

  The power transmission device 1 further includes a hydraulic first brake 7, a first clutch 8, a second brake 9, and a second clutch 10. The first brake 7, the first clutch 8, the second brake 9, and the second clutch 10 are accommodated in the case CA and are disposed radially inside the first and second ring gears R1 and R2 described above. Has been. The first planetary gear unit PS1, the first brake 7 and the first clutch 8, and the second planetary gear unit PS2, the second brake 9 and the second clutch 10 are provided symmetrically with the gear 6 described above as the center. ing.

  The 1st brake 7 is comprised with the wet friction clutch, and has the cylindrical inner 7a and the outer 7b. The inner 7a is fixed to the case CA and is arranged coaxially around the left rear shaft SRL. The inner 7a is provided with a plurality of doughnut-shaped friction plates (not shown) that are movable in the axial direction and relatively non-rotatable.

  The outer 7b is provided so as to be rotatable integrally with the first ring gear R1 through a hollow rotating shaft 11 in a coaxial manner. The outer 7b is provided with a plurality of doughnut-shaped friction plates (not shown) that are movable in the axial direction and relatively non-rotatable. These friction plates are arranged so as to alternately overlap with the friction plates of the inner 7a in the axial direction, and a slight gap is formed between the friction plates of the inner 7a and the friction plates of the inner 7a by urging by a return spring (not shown). It is kept as it is.

  In the first brake 7 configured as described above, when the hydraulic pressure from the hydraulic pump 15 to be described later is not supplied, the friction plates of the inner 7a and the outer 7b are separated from each other by the biasing force of the return spring, The brake 7 is released. On the other hand, when the hydraulic pressure is supplied to the first brake 7, the friction plates of the inner 7a and the outer 7b are thereby engaged with each other, and the first brake 7 is in the engaged state. The first ring gear R1 is braked when the first brake 7 is engaged, and released when released.

  The 1st clutch 8 is a wet friction clutch like the 1st brake 7, and has the cylindrical inner 8a and the outer 8b. The inner 8a is coaxially and integrally provided on the connecting shaft 5 and is disposed between the gear 6 and the first sun gear S1. The inner 8a is provided with a plurality of doughnut-like friction plates (not shown) that are movable in the axial direction and relatively non-rotatable.

  The outer 8b is provided so as to be rotatable coaxially and integrally with the first ring gear R1 via a hollow rotating shaft 12, and the outer 8b is disposed around the connecting shaft 5. The outer 8b is provided with a plurality of doughnut-shaped friction plates (not shown) that are movable in the axial direction and relatively non-rotatable. These friction plates are arranged so as to alternately overlap with the friction plates of the inner 8a in the axial direction, and a slight gap is formed between the friction plates of the inner 8a and the friction plate by urging by a return spring (not shown). It is kept as it is.

  In the first clutch 8 configured as described above, when the hydraulic pressure from the hydraulic pump 15 is not supplied, the friction plates of the inner 8a and the outer 8b are separated from each other by the urging force of the return spring, and the first clutch 8 Is released. On the other hand, when the hydraulic pressure is supplied to the first clutch 8, the friction plates of the inner 8a and the outer 8b are thereby engaged with each other, and the first clutch 8 is engaged. Further, the first sun gear S1 and the first ring gear R1 are connected when the first clutch 8 is engaged, and are disconnected when released.

  Since the 2nd brake 9 and the 2nd clutch 10 are each comprised similarly to the 1st brake 7 and the 1st clutch 8, the structure is demonstrated easily below. The second brake 9 and the second clutch 10 have inner 9a and 10a and outer 9b and 10b, respectively. The inner 9a of the second brake 9 is fixed to the case CA, and the outer 9b is coaxially and rotatably provided on the second ring gear R2 via a hollow rotating shaft 13. Moreover, both 9a and 9b are coaxially arrange | positioned around the right rear axis | shaft SRR.

  The second brake 9 having the above configuration is in the released state when the hydraulic pressure from the hydraulic pump 15 is not supplied, and is in the engaged state when the hydraulic pressure is supplied. The second ring gear R2 is braked when the second brake 9 is engaged, and released when released.

  The inner 10a of the second clutch 10 is provided coaxially and rotatably on the connecting shaft 5, and is disposed between the gear 6 and the second sun gear S2. The outer 10 b is coaxially and integrally provided on the second ring gear R <b> 2 via a hollow rotating shaft 14, and is disposed around the connecting shaft 5.

  The second clutch 10 configured as described above is in a released state when the hydraulic pressure from the hydraulic pump 15 is not supplied, and is in an engaged state when the hydraulic pressure is supplied. Further, the second sun gear S2 and the second ring gear R2 are connected by the engagement of the second clutch 10, and are disconnected by the release.

  Further, the power transmission device 1 is provided with a hydraulic pump 15, a first electromagnetic valve SV1, a second electromagnetic valve SV2, a third electromagnetic valve SV3, and a fourth electromagnetic valve SV4 (see FIG. 3). The hydraulic pump 15 is for pumping up the oil OIL described above and supplying hydraulic pressure to the first clutch 7, the first brake 8, the second clutch 9 and the second brake 10. As described above, the oil OIL is used as the lubricating oil for the first and second planetary gear devices PS1 and PS2 and the hydraulic oil for the first clutch 7, the first brake 8, the second clutch 9, and the second brake 10. ing.

  The first and second brakes 7 and 9 are connected to the hydraulic pump 15 via an oil passage (not shown) and first and second electromagnetic valves SV1 and SV2, respectively. The opening degree of the first electromagnetic valve SV1 is controlled by an ECU 2 (see FIG. 3) described later, whereby the hydraulic pressure supplied from the hydraulic pump 15 to the first brake 7 is adjusted, whereby the first brake 7 is engaged. The force, ie the braking force, is controlled. Similarly, the opening degree of the second electromagnetic valve SV2 is controlled by the ECU 2, whereby the hydraulic pressure supplied from the hydraulic pump 15 to the second brake 9 is adjusted, whereby the fastening force (controlling force) of the second brake 9 is adjusted. Power) is controlled.

  The first and second clutches 8 and 10 are connected to the hydraulic pump 15 via an oil passage (not shown) and third and fourth electromagnetic valves SV3 and SV4, respectively. The opening degree of the third electromagnetic valve SV3 is controlled by the ECU 2, whereby the engagement force of the first clutch 8 is controlled by adjusting the hydraulic pressure supplied from the hydraulic pump 15 to the first clutch 8. Similarly, the opening degree of the fourth electromagnetic valve SV4 is controlled by the ECU 2, whereby the hydraulic pressure supplied from the hydraulic pump 15 to the second clutch 10 is adjusted, whereby the fastening force of the second clutch 10 is controlled. Is done.

  The rotating electrical machine 4 is composed of, for example, an induction motor, and is disposed so as to overlap the planetary gear devices PS1 and PS2 in the axial direction of the first and second planetary gear devices PS1 and PS2. In the rotating electrical machine 4, when electric power is supplied, the supplied electric power is converted into motive power and output to the output shaft 4 a. When power is input to the output shaft 4a, the power is converted into electric power (power generation). The rotating electrical machine 4 is connected to a chargeable / dischargeable battery 22 via a power drive unit (hereinafter referred to as “PDU”) 21, and can exchange electric power with the battery 22. The PDU 21 is composed of an electric circuit such as an inverter. As shown in FIG. 3, the ECU 2 is electrically connected to the PDU 21, and the ECU 2 controls the PDU 21 so that power supplied to the rotating electrical machine 4, power generated by the rotating electrical machine 4, and rotation The rotational speed of the electric machine 4 is controlled.

  Hereinafter, converting electric power supplied to the rotating electrical machine 4 into power and outputting the power from the output shaft 4a is appropriately referred to as “powering”. In addition, generating power with the rotating electrical machine 4 using the power input to the output shaft 4a and converting the power into electric power is referred to as “regeneration” as appropriate.

  A gear 16 is integrally provided on the output shaft 4 a of the rotating electrical machine 4, and the gear 16 meshes with the gear 6 described above. Further, the above-described hydraulic pump 15 is provided in the middle of the output shaft 4 a of the rotating electrical machine 4. The hydraulic pump 15 is driven by the driving force of the rotating electrical machine 4 and the power transmitted from the left and right rear wheels WRL, WRR to the first and second sun gears S1, S2.

  As shown in FIG. 3, the ECU 2 receives a detection signal indicating the steering angle θ of the steering wheel of the vehicle V from the steering angle sensor 31 and a detection signal indicating the vehicle speed VP from the vehicle speed sensor 32. Further, a detection signal representing a current / voltage value input / output to / from the battery 22 is input from the current / voltage sensor 33 to the ECU 2. The ECU 2 calculates the state of charge of the battery 22 based on the detection signal from the current / voltage sensor 33.

  The ECU 2 is composed of a microcomputer including an I / O interface, CPU, RAM, ROM, and the like. In accordance with the detection signals from the various sensors 31 to 33 described above, the ECU 2 performs the rotating electrical machine 4, the first clutch 7, the first brake 8, the second clutch 9, and the second brake 10 according to a control program stored in the ROM. To control. Thereby, various operations of the power transmission device 1 are performed.

  FIG. 4 shows an operation mode of the power transmission device 1 and operations of various components in each operation mode. As shown in the figure, this operation mode includes “straight forward assist mode”, “left turn assist mode”, “right turn assist mode”, “high speed straight turn mode”, “high speed left turn mode”, “high speed right” "Swivel mode" and "High speed forward / reverse mode" are included. Hereinafter, the control operation of the ECU 2 in each operation mode will be described with reference to FIGS.

[Straight Assist Mode]
In the straight-ahead assist mode, the left and right rear wheels WRL and WRR are rotated at the same rotational speed when the engine 3 is in operation and the vehicle V is moving forward and backward at low and medium speeds. This is an operation mode in which high linear stability is ensured and the rotating electrical machine 4 assists the engine 3.

  As shown in FIG. 4, during the straight traveling assist mode, the first brake 7 is completely engaged to hold the first ring gear R1 in the stopped state and the first clutch 8 is released to thereby release the first sun gear S1. And the first ring gear R1 are cut off. Further, the second ring gear R2 is held in a stopped state by completely engaging the second brake 9, and the second clutch 10 is released to cut off the second sun gear S2 and the second ring gear R2. . Further, power running is performed by the rotating electrical machine 4. FIG. 5 shows the rotational speed relationship and the torque balance relationship between the various types of rotary elements during the straight travel assist mode.

  As described above, the rotational speeds of the first sun gear S1, the first carrier C1, and the first ring gear R1 are collinear with each other, and the rotational speeds of the second sun gear S2, the second carrier C2, and the second ring gear R2 are mutually common. There is a line relationship. Further, since the first and second sun gears S1 and S2 are connected to each other so as to be integrally rotatable, the rotational speeds of both S1 and S2 are equal to each other.

  Furthermore, since the output shaft 4a of the rotating electrical machine 4 is connected to the first and second sun gears S1 and S2 via the gear 16, the gear 6, and the connecting shaft 5, the shifting by these gears 16 and 6 is ignored. In this case, the rotational speed of the rotating electrical machine 4 is equal to that of the first and second sun gears S1 and S2. Further, since the first and second carriers C1 and C2 are connected to the left and right rear wheels WRL and WRR via the left and right rear shafts SRL and SRR, respectively, the rotation speeds of the first and second carriers C1 and C2 Are equal to the rotation speeds of the left rear wheel WRL and the right rear wheel WRR, respectively.

  From the above, the rotation speeds of the first sun gear S1, the first carrier C1, the first ring gear R1, the second sun gear S2, the second carrier C2, the second ring gear R2, the left and right rear wheels WRL, WRR, and the rotating electrical machine 4 are, for example, It is shown as in FIG. In the figure, ZS1, ZR1, ZS2, and ZR2 are the numbers of teeth of the first sun gear S1, the first ring gear R1, the second sun gear S2, and the second ring gear R2, respectively.

  During the straight travel assist mode, the output torque (hereinafter referred to as “motor torque”) of the rotating electrical machine 4 is transmitted to the hydraulic pump 15 and further transmitted to the first and second sun gears S1 and S2. As shown in FIG. 5, the motor torque TS transmitted to the first sun gear S1 is a braking force acting on the first ring gear R1 from the first brake 7 (hereinafter referred to as “first brake braking force BR1”) as a reaction torque. Is transmitted to the first carrier C1 and further transmitted to the left rear wheel WRL. Further, the motor torque TS transmitted to the second sun gear S2 uses the braking force acting on the second ring gear R2 from the second brake 9 (hereinafter referred to as “second brake braking force BR2”) as a reaction torque, and the second carrier. It is transmitted to C2 and further transmitted to the right rear wheel WRR.

  In FIG. 5, RRL and RRR are reaction force torques acting on the first and second carriers C1 and C2 from the left and right rear wheels WRL and WRR, respectively. In FIG. 5, for convenience, the motor torque transmitted to the first and second sun gears S <b> 1 and S <b> 2 is indicated by the same symbol (TS).

  As described above, as shown in FIG. 6, during the straight traveling assist mode, the driving force of the rotating electrical machine 4 is transmitted to the left and right rear wheels WRL, WRR. As a result, the rotating electrical machine 4 assists the engine 3. Further, as apparent from FIG. 5, the driving force of the rotating electrical machine 4 is transmitted to the left and right rear wheels WRL and WRR in a decelerated state, and therefore the rotating electrical machine 4 is directly connected to the left and right rear wheels WRL and WRR. A larger torque can be transmitted to the left and right rear wheels WRL, WRR. In FIG. 6 and FIGS. 8 and 10 to be described later, the power transmission state is indicated by hatching a thick line with an arrow.

  Further, as described above, the number of teeth ZS1, ZS2 of the first and second sun gears S1, S2 are equal to each other, and the number of teeth ZR1, ZR2 of the first and second ring gears R1, R2 are equal to each other. Accordingly, during the straight traveling assist mode, the first and second brakes 7 and 9 hold the first and second ring gears R1 and R2 in the stopped state as described above, so that the left and right rear wheels WRL and WRR are identical to each other. The vehicle V can be rotated at a high rotational speed, thereby ensuring high straight running stability of the vehicle V.

[Left-turn assist mode]
In the left turn assist mode, when the engine 3 is in operation and the vehicle V is turning left at low and medium speeds, the rotational speed of the right rear wheel WRR is set using the driving force of the rotating electrical machine 4. This is an operation mode in which the turning performance of the vehicle V is improved by increasing the counterclockwise yaw moment of the vehicle V by increasing the rotational speed of the WRL.

  As shown in FIG. 4, during the left turn assist mode, the first brake 7 is completely engaged to hold the first ring gear R1 in the stopped state, and the first clutch 8 is released to release the first sun gear. Shut off between S1 and the first ring gear R1. Further, by releasing the second brake 9, the braking of the second ring gear R2 by the second brake 9 is released, and the fastening force of the second clutch 10 is controlled (shown as “variable”). Further, power running is performed by the rotating electrical machine 4. FIG. 7 shows the rotational speed relationship and torque balance relationship between the various rotary elements during the left turn assist mode.

  As shown in FIG. 7, during the left turn assist mode, the motor torque of the rotating electrical machine 4 is transmitted to the hydraulic pump 15 and further to the first and second sun gears S1 and S2, as in the case of the straight assist mode. The The torque TS transmitted to the first sun gear S1 is transmitted to the first carrier C1 using the first brake braking force BR1 acting on the first ring gear R1 as a reaction torque, and further transmitted to the left rear wheel WRL. Further, the degree of connection between the second sun gear S2 and the second ring gear R2 is adjusted by controlling the fastening force of the second clutch 10, whereby a part of the torque TS transmitted to the second sun gear S2 is The torque transmitted to the two-ring gear R2 and, as a result, the torque transmitted to the second sun gear S2 and the second ring gear R2 is transmitted to the right rear wheel WRR via the second carrier C2. In FIG. 5, TR2 is the torque transmitted to the second ring gear R2.

  As described above, as shown in FIG. 8, during the left turn assist mode, the driving force of the rotating electrical machine 4 is transmitted to the left and right rear wheels WRL and WRR. As a result, the rotating electrical machine 4 assists the engine 3. In this case, as is apparent from the relationship between the rotational speeds shown in FIG. 7, the driving force (torque × rotational speed) distributed (transmitted) from the rotating electrical machine 4 to the right rear wheel WRR is distributed to the left rear wheel WRL. It becomes larger than the driving force. Further, the driving force (rotation speed) transmitted to the right rear wheel WRR can be freely controlled by controlling the fastening force of the second clutch 10. As described above, the counterclockwise yaw moment of the vehicle V can be increased and, consequently, the turning performance can be improved. When the second clutch 10 is completely engaged, the second sun gear S2, the second carrier C2, and the second ring gear R2 rotate together.

[Right turn assist mode]
In the right turn assist mode, when the engine 3 is in operation and the vehicle V is turning right at low and medium speeds, the rotational speed of the left rear wheel WRL is set to the right using the driving force of the rotating electrical machine 4. This is an operation mode in which the turning performance of the vehicle V is improved by increasing the rotational speed of the rear wheel WRR and increasing the clockwise yaw moment of the vehicle V.

  As shown in FIG. 4, during the right turn assist mode, by releasing the first brake 7, the braking of the first ring gear R <b> 1 by the first brake 7 is released and the fastening force of the first clutch 8 is controlled. (Shown as “variable”). Further, the second ring gear R2 is held in a stopped state by completely engaging the second brake 9, and the second clutch 10 is released to cut off the second sun gear S2 and the second ring gear R2. . Further, power running is performed by the rotating electrical machine 4.

  Since the operations of the various rotating elements in the right turn assist mode are performed in the left and right direction opposite to the left turn assist mode, detailed description thereof is omitted. Further, during the right turn assist mode, the driving force (number of rotations) distributed from the rotating electrical machine 4 to the left rear wheel WRL is larger than the driving force distributed to the right rear wheel WRR. Furthermore, the power transmitted to the left rear wheel WRL (the number of rotations of the left rear wheel WRL) can be freely controlled by controlling the fastening force of the first clutch 8. As described above, the clockwise yaw moment of the vehicle V can be increased, and the turning performance thereof can be improved. When the first clutch 8 is completely engaged, the first sun gear S1, the first carrier C1, and the first ring gear R1 rotate together.

[High speed straight running mode]
This high-speed straight-ahead mode is an operation mode for ensuring that the vehicle V has high straight-ahead stability by rotating the left and right rear wheels WRL and WRR at the same rotation speed when the vehicle V is moving forward at a high speed. is there.

  As shown in FIG. 4, during the high-speed straight-ahead mode, the control of the first brake 7, the first clutch 8, the second brake 9 and the second clutch 10 is performed in the same manner as in the above-described straight-aid assist mode. Compared to the mode, only the rotating electric machine 4 is controlled to be stopped. Therefore, high straight running stability of the vehicle V can be ensured as in the straight running assist mode.

  Further, the high-speed straight-ahead mode is set as an operation mode mainly after setting the straight-ahead assist mode. In this case, the rotating electrical machine 4 that has been performing power running during the straight-ahead assist mode is stopped along with the transition of the operation mode to the high-speed straight-ahead mode, but the first and second brakes 7 and 9 are used. By braking the ring gears R1 and R2, the power of the left and right rear wheels WRL and WRR can be transmitted to the hydraulic pump 15 via the first and second carriers C1 and C2 and the first and second sun gears S1 and S2. it can. As a result, the hydraulic pump 15 can be continuously driven even after the transition from the straight-ahead assist mode to the high-speed straight-ahead mode, so that the hydraulic pressure can be supplied to the first and second brakes 7 and 9 without any trouble. it can.

  In this case, since the hydraulic pump 15 is connected to both the first and second sun gears S1, S2, the load of the hydraulic pump 15 is not applied to only one of the left and right rear wheels WRL, WRR. Therefore, it is possible to ensure higher straight running stability of the vehicle V. Furthermore, although a part of the power of the left and right rear wheels WRL, WRR is transmitted to the rotating electrical machine 4, the rotating electrical machine 4 is composed of an induction motor, so that it can generate power unless the PDU 21 is actively controlled. Therefore, the braking torque generated by power generation does not act on the left and right rear wheels WRL, WRR, and the accompanying resistance can be suppressed.

[High-speed left turn mode]
In this high-speed left turn mode, when the vehicle V is turning left at high speed, power is transferred between the left and right rear wheels WRL and WRR, so that the number of rotations of the right rear wheel WRR is reduced. This is an operation mode for improving the turning performance of the vehicle V by increasing the counterclockwise yaw moment of the vehicle V by increasing the rotational speed.

  As shown in FIG. 4, during the high-speed left turn mode, the control of the first clutch 7, the first brake 8, the second clutch 9 and the second brake 10 is performed in the same way as in the left turn assist mode described above. Compared with the left turn assist mode, only the rotating electric machine 4 is controlled to be stopped. FIG. 9 shows the rotational speed relationship and the torque balance relationship between the various rotary elements during the high-speed left turn mode.

  As shown in FIG. 9, during the high-speed left turn mode, the torque TRL transmitted from the left rear wheel WRL to the first carrier C1 uses the first brake braking torque BR1 acting on the first ring gear R1 as a reaction torque. 1 is transmitted to the sun gear S1, and further transmitted to the second sun gear S2, the hydraulic pump 15, and the rotating electrical machine 4 (see FIG. 10). In FIG. 9, RS1 is a reaction torque acting on the first sun gear S1, TS2 is a torque transmitted to the second sun gear S2, and the magnitudes of both are equal to each other.

  The torque TS2 transmitted to the second sun gear S2 is transmitted to the second ring gear R2 via the second clutch 10. As a result, the torque obtained by combining the torques TS2 and TR2 transmitted to the second sun gear S2 and the second ring gear R2 is transmitted to the right rear wheel WRR via the second carrier C2 and the right rear shaft SRR.

  As described above, as shown in FIG. 10, a part of the power of the left rear wheel WRL is transmitted to the right rear wheel WRR via the first and second planetary gear units PS1 and PS2. In other words, a braking force acts on the left rear wheel WRL and a driving force acts on the right rear wheel WRR. In this case, as is apparent from FIG. 9, by controlling the fastening force of the second clutch 10, the power transmitted from the left rear wheel WRL to the right rear wheel WRR (the number of rotations of the right rear wheel WRR) can be freely set. Therefore, the counterclockwise yaw moment of the vehicle V can be increased, and the turning performance thereof can be improved. When the second clutch 10 is completely engaged, the second sun gear S2, the second carrier C2, and the second ring gear R2 rotate together.

  Further, during the high-speed left turn mode, the rotating electrical machine 4 is stopped as in the high-speed straight-ahead mode. However, as the power is transmitted from the left rear wheel WRL to the right rear wheel WRR, the hydraulic pump 15 is also moved to the left rear. Since a part of the power of the wheel WRL is transmitted, it is possible to supply hydraulic pressure to the first brake 7 and the second clutch 10 without any trouble. Furthermore, since the load of the hydraulic pump 15 can be applied to both the left and right rear wheels WRL and WRR, higher running stability of the vehicle V can be ensured. In addition, although a part of the power of the left rear wheel WRL is transmitted to the rotating electrical machine 4, since the rotating electrical machine 4 is constituted by an induction motor, the accompanying resistance can be suppressed.

[High-speed right turn mode]
In this high-speed right turn mode, when the vehicle V is turning right at high speed, power is exchanged between the left and right rear wheels WRL, WRR, whereby the number of rotations of the left rear wheel WRL is set to the right rear wheel. This is an operation mode for improving the turning performance of the vehicle V by increasing the rotational speed of the WRR and increasing the clockwise yaw moment of the vehicle V.

  As shown in FIG. 4, during the high-speed right turn mode, the control of the first clutch 7, the first brake 8, the second clutch 9, and the second brake 10 is performed in the same way as in the right turn assist mode described above. However, it differs from the left turn assist mode only in controlling the rotating electrical machine 4 to the stop state.

  Since the operations of the various rotating elements in the high-speed right turn mode are performed in the left-right direction opposite to the high-speed left turn mode, detailed description thereof is omitted. In addition, during the high-speed right turn mode, the power transmitted from the right rear wheel WRR to the left rear wheel WRL (the number of rotations of the left rear wheel WRL) is freely controlled by controlling the engagement force of the first clutch 8. Therefore, the clockwise yaw moment of the vehicle V can be increased, and the turning performance thereof can be improved. When the first clutch 8 is completely engaged, the first sun gear S1, the first carrier C1, and the first ring gear R1 rotate together.

  Further, during the high-speed right turn mode, the rotary electric machine 4 is stopped as in the case of the high-speed straight-ahead mode. However, as the power is transmitted from the right rear wheel WRR to the left rear wheel WRL, the hydraulic pump 15 Since a part of the power of the rear wheel WRR is transmitted, it is possible to supply hydraulic pressure to the second brake 9 and the first clutch 8 without any trouble. Furthermore, since the load of the hydraulic pump 15 can be applied to both the left and right rear wheels WRL and WRR, higher running stability of the vehicle V can be ensured. Furthermore, although a part of the power of the right rear wheel WRR is transmitted to the rotating electrical machine 4, since the rotating electrical machine 4 is composed of an induction motor, the accompanying resistance can be suppressed.

[High speed forward / reverse mode]
The high speed forward / reverse mode is an operation mode performed when the vehicle V is moving forward / reverse at high speed.

  As shown in FIG. 4, the first brake 7, the first clutch 8, the second brake 9, and the second clutch 10 are completely released during the high speed forward / reverse mode. Thus, as is apparent from the alignment chart shown in FIG. 5 and the like, the left and right rear wheels WRL and WRR can be differentially rotated while the vehicle V is traveling.

  Further, the friction of the hydraulic pump 15 acting on the first and second sun gears S1 and S2 is larger than the reaction force (friction) of the first and second ring gears R1 and R2. For this reason, even if power is transmitted from the left and right rear wheels WRL and WRR to the first and second carriers C1 and C2, the first and second ring gears R1 and R2 only rotate idly, and the left and right rear wheels WRL and WRR Is not transmitted wastefully to the hydraulic pump 15 and the rotating electrical machine 4 via the first and second sun gears S1 and S2, and both 15 and 4 are held in a stopped state.

  Since the hydraulic pump 15 cannot be driven using the power of the left and right rear wheels WRL and WRR as described above during the high speed forward / reverse mode, the high speed straight forward mode, the high speed left turn mode, and the high speed When the operation mode shifts to the right turn mode, the rotating electrical machine 4 is forced to perform power running in order to drive the hydraulic pump 15. Then, after shifting to the high-speed straight-ahead mode, the high-speed left-turn mode, and the high-speed right-turn mode, the hydraulic pressure of the hydraulic pump 15 is sufficiently raised by the power running of the rotating electric machine 4 and the first or second brake 7 or 9 is engaged. After that, the rotating electrical machine 4 is stopped.

  FIG. 11 shows processing for setting an operation mode when the vehicle V is turning. This process is executed every predetermined time from the start of turning of the vehicle V to the end thereof. First, in step 1 (illustrated as “S1”, the same applies hereinafter), it is determined whether or not the detected vehicle speed VP is equal to or higher than a predetermined vehicle speed. If the answer is yes, it is determined that the vehicle V is traveling at a high speed and it is determined whether or not the turning direction of the vehicle V is the right direction (step 2). This determination is made based on the detected steering angle θ of the steering wheel.

  When the answer to step 2 is YES, that is, when the vehicle V is turning right at high speed, the operation mode is set to the above-described high-speed right turning mode (step 3), and this process is terminated. On the other hand, when the answer to step 2 is NO, that is, when the vehicle V is turning left at high speed, the operation mode is set to the above-described high-speed left turning mode (step 4), and this process ends.

  On the other hand, if the answer to step 1 is NO and the vehicle V is not traveling at high speed, it is determined whether or not the turning direction of the vehicle V is the right direction (step 5). This determination is performed in the same manner as in step 2 above. When the answer to step 5 is YES, that is, when the vehicle V is turning right at low / medium speed, the operation mode is set to the right turn assist mode described above (step 6), and this process is terminated. .

  On the other hand, when the answer to step 5 is NO, that is, when the vehicle V is turning left at low / medium speed, the operation mode is set to the left turn assist mode described above (step 7), and this process ends. .

  The correspondence between various elements in the present embodiment and various elements in the present invention is as follows. That is, the left and right rear wheels WRL and WRR in the present embodiment correspond to the first and second wheels in the present invention, respectively, and the ECU 2 in the present embodiment corresponds to the first and second control means in the present invention. The rotating electrical machine 4 and the engine 3 in the present embodiment correspond to the first and second prime movers in the present invention, respectively.

  In addition, the first sun gear S1, the first carrier C1, and the first ring gear R1 in the present embodiment correspond to the first rotating element, the second rotating element, and the third rotating element in the present invention, respectively, and the second sun gear S2, The second carrier C2 and the second ring gear R2 correspond to the fourth rotating element, the fifth rotating element, and the sixth rotating element in the present invention, respectively. Further, the first brake 7, the first clutch 8, the second brake 9, and the second clutch 10 in the present embodiment are the first braking means, the first connecting / disconnecting means, the second braking means, and the second connecting / disconnecting according to the present invention. It corresponds to each means. The hydraulic pump 15 in the present embodiment corresponds to the fluid pressure supply device in the present invention, and the left and right front wheels WFL, WFR in the present embodiment correspond to the third wheel in the present invention.

  As described above, according to the present embodiment, when the rotational speed of the right rear wheel WRR is made higher than the rotational speed of the left rear wheel WRL during the high-speed left turn mode (FIGS. 9 and 10), the first brake 7 is engaged, the second brake 9 is released, the first clutch 8 is released, and the engagement force of the second clutch 10 is controlled. On the contrary, in the high-speed right turn mode, when the rotation speed of the left rear wheel WRL is made higher than the rotation speed of the right rear wheel WRR, the second brake 9 is engaged and the first brake 7 is released. At the same time, the second clutch 10 is released, and the fastening force of the first clutch 8 is controlled. As described above, power can be appropriately transmitted between the left and right rear wheels WRL and WRR during the high speed left turn mode and the high speed right turn mode, so the power of the left and right rear wheels WRL and WRR can be freely set. This can be changed, and the turning performance of the vehicle V can be improved.

  Similarly, in the left turn assist mode (FIGS. 7 and 8), when the rotational speed of the right rear wheel WRR is made higher than the rotational speed of the left rear wheel WRL, power is performed by the rotating electrical machine 4 and the first brake 7 is engaged, the second brake 9 is released, the first clutch 8 is released, and the engagement force of the second clutch 10 is controlled. On the contrary, during the right turn assist mode, when the rotational speed of the left rear wheel WRL is made higher than the rotational speed of the right rear wheel WRR, power is performed by the rotating electrical machine 4 and the second brake 9 is engaged. Then, the first brake 7 is released, the second clutch 10 is released, and the fastening force of the first clutch 8 is controlled. As described above, the driving force (number of rotations) distributed from the rotating electrical machine 4 to the left and right rear wheels WRL, WRR can be freely changed, and therefore the turning performance of the vehicle V can be improved.

  Further, as apparent from the comparison between FIG. 13, FIG. 7 and FIG. 9, the conventional power transmission described above during the left turn assist mode, right turn assist mode, high speed left turn mode and high speed right turn mode. Compared with the case where the braking force of the second left (right) brake is applied directly to the left (right) caterpillar as in the device, the torque acting on the first and second brakes 7, 9 can be reduced. . Therefore, the first and second brakes 7 and 9 can be downsized. Similarly, since the torque acting on the first and second clutches 8 and 10 can be reduced as compared with the conventional case, the size of the first and second clutches 8 and 10 can be reduced. As described above, the power transmission device 1 as a whole can be downsized.

  Further, during the high-speed forward / reverse mode, the first and second brakes 7, 9 and the first and second clutches 8, 10 are disengaged so that the left and right rear wheels WRL, WRR are held in a state where they can rotate relative to each other. can do.

  Further, the first and second brakes 7 and 9 and the first and second clutches 8 and 10 are operated by supply of hydraulic pressure from the hydraulic pump 15. Further, since the hydraulic pump 15 is connected to the first and second sun gears S1 and S2 to which the rotating electrical machine 4 is connected, the hydraulic pump 15 can be driven by the driving force of the rotating electrical machine 4. Therefore, it is not necessary to provide a separate drive device for driving the hydraulic pump 15, and accordingly, the entire power transmission device 1 can be reduced in size.

  Further, when the operation mode is shifted from the high speed forward / reverse mode to the high speed straight mode, the high speed left turn mode, and the high speed right turn mode, the rotating electric machine 4 forcibly performs power running to drive the hydraulic pump 15. Is called. Then, after shifting to the high-speed straight-ahead mode, the high-speed left-turn mode, and the high-speed right-turn mode, the hydraulic pressure of the hydraulic pump 15 is sufficiently raised by the power running of the rotating electric machine 4 and the first or second brake 7 or 9 is engaged. After that, the rotating electrical machine 4 is stopped. Therefore, even if the rotating electrical machine 4 is stopped after the transition from the high speed forward / reverse mode to the high speed straight mode, the high speed left turn mode, and the high speed right turn mode, the power of the left and right rear wheels WRL, WRR The hydraulic pump 15 can be driven appropriately.

  Furthermore, in this case, since the hydraulic pump 15 is connected to both the first and second sun gears S1 and S2, the load of the hydraulic pump 15 can be applied to both the left and right rear wheels WRL and WRR. The high running stability of the vehicle V can be ensured. Moreover, since the rotary electric machine 4 is comprised with the induction motor, the accompanying resistance can be suppressed.

  Furthermore, the first and second brakes 7 and 9 are engaged when the left and right rear wheels WRL and WRR are rotated at the same rotational speed in the straight traveling assist mode (FIGS. 5 and 6) and in the high speed straight traveling mode. At the same time, the first and second clutches 8 and 10 are released. Further, the number of teeth ZS1, ZS2 of the first and second sun gears S1, S2 are set to the same value, and the number of teeth ZR1, ZR2 of the first and second ring gears R1, R2 are set to the same value. Yes. As described above, the left and right rear wheels WRL, WRR can be rotated at the same rotational speed, and therefore, high straight running stability of the vehicle V can be ensured.

  In addition, since the first and second brakes 7 and 9 are held in the engaged state during the straight-ahead assist mode and the high-speed straight-ahead mode, when shifting from this state to the high-speed left turn mode or the high-speed right turn mode, It is only necessary to stop the supply of hydraulic pressure to one of the first and second brakes 7 and 9, and it is not necessary to supply hydraulic pressure to the other of the first and second brakes 7 and 9 from the beginning. Transfer of power between the wheels WRL and WRR can be started early. Similarly, when changing to the left turn assist mode or the right turn assist mode, the change of the driving force transmitted from the rotating electrical machine 4 to the left and right rear wheels WRL, WRR can be started early.

  Further, the oil OIL that is the hydraulic oil of the hydraulic pump 15 is also used as the lubricating oil of the power transmission device 1, and the first and second brakes 7, 7 are always in the straight travel assist mode and the high speed straight travel mode. In order to fasten 9, hydraulic pressure is supplied from both hydraulic pumps 15 to both 7 and 9. As a result, the amount of oil OIL stored in the case CA of the power transmission device 1 can be reduced, so that the first and second sun gears S1, the first and second ring gears R1, R2, and the first and second The stirring resistance of the oil OIL when the carriers C1 and C2 rotate can be suppressed.

  Further, since the left and right front wheels WFL, WFR are driven by the engine 3 and are configured to be able to change the steering direction, the turning performance of the vehicle V can be further improved.

  Further, since the first and second brakes 7 and 9 and the first and second clutches 8 and 10 are arranged on the inner side in the radial direction than the first and second ring gears R1 and R2, the entire power transmission device 1 is arranged. The size in the radial direction can be reduced.

  Further, since the rotating electrical machine 4 having higher responsiveness than the internal combustion engine is used, the responsiveness of driving the left and right rear wheels WRL and WRR by the rotating electrical machine 4 can be enhanced.

  Further, the first and second planetary gear devices PS1 and PS2 are arranged on the same axis, and the first and second planetary gear devices PS1 and PS2 and the rotating electrical machine 4 are over each other in the axial direction. Since it arrange | positions so that it may wrap, the magnitude | size of the radial direction of the whole power transmission device 1 can be made small.

  Next, a power transmission device 51 according to a second embodiment of the present invention will be described with reference to FIG. The power transmission device 51 is mainly different from the first embodiment in the configuration of a first brake 52, a first clutch 53, a second brake 54, and a second clutch 55. In FIG. 12, the same components as those in the first embodiment are denoted by the same reference numerals. Hereinafter, a description will be given focusing on differences from the first embodiment.

  The first brake 52, the first clutch 53, the second brake 54, and the second clutch 55 are hydraulic, similar to the first brake 7, the first clutch 8, the second brake 9, and the second clutch 10 of the first embodiment. The wet friction clutch has inner 52a, 53a, 54a and 55a and outer 52b, 53b, 54b and 55b. The basic configurations of the inners 52a, 53a, 54a and 55a and the outers 52b, 53b, 54b and 55b are the same as in the first embodiment (the friction plate is provided). Only points different from the form will be described.

  The inner 52a of the first brake 52 is fixed to the case CA, and is arranged coaxially around the first ring gear R1. The outer 52b is coaxially attached to the outer periphery of the first ring gear R1, and is rotatable integrally with the first ring gear R1.

  The inner 53a of the first clutch 53 is connected to the connecting shaft 5 described in the first embodiment via a hollow rotating shaft 61 and a flange 62, and the connecting shaft 5, the first and second sun gears S1, S2 are connected. And can be rotated together. Further, the inner 53a is arranged coaxially around the first ring gear R1. The outer 53b is coaxially attached to the outer periphery of the first ring gear R1, and is rotatable integrally with the first ring gear R1. Further, the outer 53b overlaps the outer 52b of the first brake 52 in the axial direction.

  The inner 54a of the second brake 54 is fixed to the case CA and is arranged coaxially around the second ring gear R2. The outer 54b is coaxially attached to the outer periphery of the second ring gear R2, and is rotatable integrally with the second ring gear R2.

  The inner 55a of the second clutch 55 is connected to the connecting shaft 5 via a hollow rotating shaft 63 and a flange 64, and is rotatable together with the connecting shaft 5, the first and second sun gears S1, S2. . The inner 55a is coaxially disposed around the second ring gear R2. The outer 55b is coaxially attached to the outer peripheral portion of the second ring gear R2, and is rotatable integrally with the second ring gear R2. Further, the outer 55b overlaps the outer 54b of the second brake 54 in the axial direction.

  According to the power transmission device 51 having the above configuration, the control operation described in the first embodiment is performed in the same manner for the first brake 52, the first clutch 53, the second brake 54, and the second clutch 55. Therefore, the effect by 1st Embodiment can be acquired similarly. Further, the first brake 52 and the first clutch 53 can be arranged around the first ring gear R1, and the second brake 54 and the second clutch 55 can be arranged around the second ring gear R2, respectively. As a result, the entire power transmission device 51 can be downsized by the amount that the rotating shafts 11 and 13 described in the first embodiment can be omitted. For the same reason, a hydraulic circuit (not shown) for supplying hydraulic pressure to the first brake 52, the first clutch 53, the second brake 54, and the second clutch 55 can be collectively arranged.

  Further, the first and second brakes 52 and 54 and the first and second clutches 53 and 55 in the second embodiment correspond to the first and second braking means and the first and second connection / disconnection means in the present invention, respectively. To do.

  The present invention is not limited to the first and second embodiments described below (hereinafter collectively referred to as “embodiments”), and can be implemented in various modes. For example, in the embodiment, the first and second brakes 7 and 9 and the first and second clutches 8 and 10 are of a type that is fastened by supplying hydraulic pressure, but may be of a released type. In the embodiment, during the left turn assist mode, during the right turn assist mode, during the high speed left turn mode and during the high speed right turn mode, the first or second brake 7, 9 is completely engaged. The fastening force may be controlled without completely fastening.

  Furthermore, in the embodiment, the hydraulic pump 15 is directly connected to the output shaft 4a of the rotating electrical machine 4, but may be connected via a gear. In the embodiment, the first and second brakes 7 and 9 and the first and second clutches 8 and 10 are of the type using hydraulic pressure as a power source, but other fluid pressures are used as the power source. You may use the type to do. Furthermore, in the embodiment, the first and second brakes 7, 9 and the first and second clutches 8, 10 are hydraulic, but may be electromagnetic.

  In the embodiment, the number of teeth ZS1 and ZS2 of the first and second sun gears S1 and S2 are set to the same value, and the number of teeth ZR1 and ZR2 of the first and second ring gears R1 and R2 are set to the same value. However, the ratio between the number of teeth ZS1 of the first sun gear S1 and the number of teeth ZR1 of the first ring gear R1, and the ratio of the number of teeth ZS2 of the second sun gear S2 and the number of teeth ZR2 of the second ring gear R2 are: If they are set to the same value, ZS1 and ZS2 need not be set to the same value, and ZR1 and ZR2 need not be set to the same value.

  Further, in the embodiment, the first and second sun gears S1 and S2 are connected to each other so as to be integrally rotatable, and the first and second ring gears R1 and R2 are connected to the first and second brakes 7 and 9, respectively. On the contrary, the first and second ring gears R1 and R2 are connected to each other so as to be integrally rotatable, and the first and second sun gears S1 and S2 are connected to the first and second brakes 7 and 9, respectively. You may connect. In the embodiment, the first and second planetary gear devices PS1 and PS2 are single pinion type, but may be double pinion type or bevel gear type.

  Further, in the embodiment, the first and second carriers C1 and C2 are connected to the left and right rear wheels WRL and WRR via the left and right rear shafts SRL and SRR, respectively, but are connected via gears. Also good. In the embodiment, the rotary electric machine 4 constituted by an induction motor is used as the first prime mover of the present invention. However, other prime movers capable of outputting driving force, for example, synchronous motors, internal combustion engines, external combustion An institution may be used. Furthermore, in the embodiment, the engine 3 that is a gasoline engine is used as the second prime mover of the present invention, but other prime movers such as a rotating electrical machine or an external combustion engine may be used. Alternatively, the engine 3 or the rotating electrical machine 4 may be omitted.

  In the embodiment, the first and second wheels of the present invention are the left and right rear wheels WRL and WRR, respectively, but may be the left and right front wheels WFL and WFR, or the front and rear wheels of an all-wheel drive vehicle. But you can. In addition, it is possible to appropriately change the detailed configuration within the scope of the gist of the present invention.

V Vehicle WFL Left front wheel (third wheel)
WFR Right front wheel (third wheel)
WRL Left rear wheel (first wheel)
WRR Right rear wheel (second wheel)
DESCRIPTION OF SYMBOLS 1 Power transmission device 2 ECU (1st control means, 2nd control means)
3 Engine (second prime mover)
4 Rotating electric machine (1st prime mover)
PS1 First planetary gear unit S1 First sun gear (first rotating element)
R1 1st ring gear (3rd rotating element)
C1 first carrier (second rotating element)
PS2 Second planetary gear unit S2 Second sun gear (fourth rotating element)
R2 Second ring gear (sixth rotating element)
C2 2nd carrier (5th rotating element)
7 First brake (first braking means)
8 First clutch (first connecting / disconnecting means)
9 Second brake (second braking means)
10 Second clutch (second connecting / disconnecting means)
15 Hydraulic pump (fluid pressure supply device)
51 Power transmission device 52 First brake (first braking means)
53 1st clutch (1st connection / disconnection means)
54 Second brake (second braking means)
55 Second clutch (second connecting / disconnecting means)

Claims (9)

A power transmission device capable of transmitting power between a first wheel and a second wheel of a vehicle,
It has a 1st rotation element, a 2nd rotation element, and a 3rd rotation element, and the rotation speed of the said 1st-3rd rotation element satisfies the collinear relationship arranged in this order on a single straight line in a collinear diagram A first planetary gear set configured to:
It has a 4th rotation element, a 5th rotation element, and a 6th rotation element, and the rotation speed of the said 4th-6th rotation element satisfies the collinear relationship arranged in this order on a single straight line in a collinear diagram A second planetary gear set configured to:
A first braking means connected to the third rotating element, brakes the third rotating element by fastening, and releases the braking by releasing;
A second braking means connected to the sixth rotating element, brakes the sixth rotating element by fastening, and releases the braking by releasing;
A first connecting / disconnecting means connected to the first and third rotating elements, and connected and disconnected between the first rotating element and the third rotating element by fastening and releasing;
A second connecting / disconnecting means connected to the fourth and sixth rotating elements, and connected and disconnected between the fourth rotating element and the sixth rotating element by fastening and releasing;
The first and fourth rotating elements are connected to each other so as to be integrally rotatable,
The second rotation element is connected to the first wheel, and the fifth rotation element is connected to the second wheel. A first prime mover capable of outputting a driving force;
The power transmission device according to claim 1, wherein the first and fourth rotating elements are connected to the first prime mover. The first and second braking means and the first and second connecting / disconnecting means operate by supplying fluid pressure,
The apparatus further comprises a fluid pressure supply device connected to the first and fourth rotating elements and configured to supply fluid pressure to the first and second braking means and the first and second connecting / disconnecting means. The power transmission device according to claim 1 or 2. One rotational element of the second and fifth rotational elements connected to the one wheel when the rotational speed of one of the first and second wheels is higher than the rotational speed of the other wheel; One of the first and second braking means connected to one of the third and sixth rotating elements whose rotational speed is collinear is fastened and the other of the first and second braking means is Release
The first and second rotating elements connected to the one rotating element of the third and sixth rotating elements and the one rotating element of the first and fourth rotating elements that are collinear with the one rotating element. 4. The apparatus according to claim 1, further comprising first control means for releasing one of the two connection / disconnection means and controlling the fastening force of the other of the first and second connection / disconnection means. The power transmission device described.   And a second control means for fastening the first and second braking means and releasing the first and second connecting / disconnecting means when the first and second wheels are rotated at the same rotational speed. The power transmission device according to claim 1, comprising: a power transmission device according to claim 1. The first and second wheels are the left and right wheels of the vehicle, respectively.
In addition to the first and second wheels, the vehicle is provided with a third wheel capable of operating the steering direction, and a second prime mover different from the first prime mover for driving the third wheel. The power transmission device according to claim 1, wherein the power transmission device is provided.   7. The first and second braking means and the first and second connecting / disconnecting means are disposed radially inward of the third and sixth rotating elements. The power transmission device according to any one of the above.   The power transmission device according to any one of claims 2 to 7, wherein the first prime mover is a rotating electric machine. The first and second planetary gear devices are arranged on the same axis line,
The said 1st and 2nd planetary gear apparatus and the said 1st prime mover are arrange | positioned so that it may mutually overlap in the direction of the said axis line, The one in any one of Claim 2 thru | or 8 characterized by the above-mentioned. Power transmission device.

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