JP2013032804A - In-wheel motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-wheel motor that reduces energy loss.SOLUTION: An electric vehicle drive device 10 includes a first motor 11, a second motor 12, a transmission mechanism 13, a speed reducing mechanism 40, and a clutch device 60. A first planetary gear mechanism 20 of the transmission mechanism 13 is a single-pinion planetary gear device. A second planetary gear mechanism 30 of the transmission mechanism 13 is a double-pinion planetary gear device. The speed reducing mechanism 40 includes a third sun gear 41, a fourth pinion gear 42, a third carrier 43, and a third ring gear 44.

Description

  The present invention relates to an in-wheel motor that drives an electric vehicle.

  Among the electric vehicle driving devices, those that directly drive the wheels are called in-wheel motors. An in-wheel motor here is a drive device provided in the vicinity of the wheel with which an electric vehicle is equipped. Note that the in-wheel motor is not necessarily housed in the wheel. The in-wheel motor needs to be disposed inside the wheel or in the vicinity of the wheel. However, the interior of the wheel and the vicinity of the wheel are relatively narrow spaces. Therefore, the in-wheel motor is required to be downsized.

  There are two types of in-wheel motors, one with a reduction mechanism and the other with a direct drive method without a reduction mechanism. An in-wheel motor having a speed reduction mechanism easily secures a sufficient rotational force to drive an electric vehicle when the electric vehicle starts or climbs (when climbing a hill). However, since the in-wheel motor of a system provided with a speed reduction mechanism transmits a rotational force to the wheel via the speed reduction mechanism, friction loss occurs in the speed reduction mechanism. In an in-wheel motor provided with a speed reduction mechanism, the rotational speed of the output shaft of the motor is always faster than the rotational speed of the wheel. Therefore, in an in-wheel motor having a speed reduction mechanism, energy loss increases due to friction loss in the speed reduction mechanism, particularly when the electric vehicle travels at a high speed.

  On the other hand, the direct drive type in-wheel motor transmits the rotational force to the wheel without going through the speed reduction mechanism, so that energy loss can be reduced. However, the direct drive type in-wheel motor cannot amplify the rotational force by the speed reduction mechanism. As a result, the direct drive in-wheel motor is difficult to ensure sufficient rotational force to drive the electric vehicle when the electric vehicle starts or climbs. As a technique for ensuring a sufficient rotational force for driving an electric vehicle, for example, Patent Document 1 discloses a technique that is not an in-wheel motor, but includes a speed reduction mechanism including a planetary gear mechanism and two motors. Is described.

Japanese Patent Laying-Open No. 2005-081932

  The technique described in Patent Document 1 has a power circulation path. The technique described in Patent Document 1 first converts a rotational force into electric power in a power circulation path, and converts the electric power into rotational force again. Therefore, the technique described in Patent Document 1 needs to include a generator and a motor in the power circulation path. However, as described above, the in-wheel motor is required to reduce the size of the electric vehicle drive device, and it is difficult to secure a space for installing the generator and the motor near the wheel. Moreover, the technique described in Patent Document 1 converts power into electric power, and further converts electric power into power. For this reason, the technique described in Patent Document 1 causes energy loss during energy conversion.

  The present invention has been made in view of the above, and an object thereof is to provide an in-wheel motor that can reduce energy loss.

  The present invention provides a first motor, a second motor, a first sun gear coupled to the first motor, a first pinion gear meshing with the first sun gear, and the first pinion gear so that the first pinion gear can rotate. And a first carrier that holds the first pinion gear so that the first pinion gear can revolve around the first sun gear, a clutch device that can restrict the rotation of the first carrier, and the first pinion gear. A first ring gear coupled to the second motor, a second sun gear coupled to the first motor, a second pinion gear meshed with the second sun gear, and the second pinion gear. The meshed third pinion gear, the second pinion gear, and the third pinion gear can each rotate, and the second pinion gear and the third pinion The second pinion gear and the third pinion gear are held so that the gear can revolve around the second sun gear, and the second carrier connected to the first ring gear and the third pinion gear mesh with each other. A second ring gear; a third sun gear coupled to the second ring gear; a fourth pinion gear meshing with the third sun gear; and the fourth pinion gear so that the fourth pinion gear can rotate. Holds the fourth pinion gear so that it can revolve around the third sun gear, meshes with the third carrier connected to the wheel of the electric vehicle, and the fourth pinion gear, and is fixed to the stationary system. And a third ring gear.

  With this configuration, the in-wheel motor can realize two shift states, a first shift state and a second shift state. In the first speed change state, the first motor and the second motor operate, and the clutch device is in an engaged state. In the first speed change state, the in-wheel motor has a part of the rotational force returned from the second carrier to the first ring gear, and the rotational force transmitted to the first ring gear is transmitted to the second sun gear via the first sun gear. It is transmitted. That is, in this in-wheel motor, the rotational force circulates. With such a structure, the in-wheel motor can realize a larger gear ratio. That is, the in-wheel motor can transmit a rotational force larger than the rotational force output by the first motor to the wheel in the first speed change state.

  In the second speed change state, the first motor and the second motor operate, and the clutch device is in a non-engagement state. The in-wheel motor can continuously change the gear ratio by changing the angular speed of the second motor in the second speed change state. By doing in this way, this in-wheel motor can reduce the difference between the angular velocity of the first motor and the angular velocity of the second ring gear serving as the output shaft, so that the friction loss can be reduced, resulting in the loss of energy. Can be reduced.

  The in-wheel motor has a speed reduction mechanism including a third sun gear, a fourth pinion gear, a third carrier, and a third ring gear. Since this in-wheel motor can amplify the rotational force of the first motor and the second motor by the speed reduction mechanism, the rotational force required for the first motor and the second motor can be reduced. As a result, since the first motor and the second motor can be reduced in size and weight, the in-wheel motor can be reduced in size and weight.

  The present invention provides a first motor, a second motor, a first sun gear coupled to the first motor, a first pinion gear meshing with the first sun gear, and the first pinion gear so that the first pinion gear can rotate. A first carrier that holds the first pinion gear so that the first pinion gear can revolve around the first sun gear; a first ring gear that meshes with the first pinion gear; and the first motor; The second sun gear to be coupled, the second pinion gear that meshes with the second sun gear, the third pinion gear that meshes with the second pinion gear, the second pinion gear, and the third pinion gear so that they can rotate. And the second pinion gear and the third pinion gear so that the second pinion gear and the third pinion gear can revolve around the second sun gear. A second carrier that holds the gear, a clutch device that can regulate the rotation of the second carrier, the third pinion gear meshes with the first carrier, and is connected to the second motor. A second ring gear; a third sun gear coupled to the first ring gear; a fourth pinion gear meshing with the third sun gear; and the fourth pinion gear so that the fourth pinion gear can rotate. Holds the fourth pinion gear so that it can revolve around the third sun gear, meshes with the third carrier connected to the wheel of the electric vehicle, and the fourth pinion gear, and is fixed to the stationary system. And a third ring gear.

  With this configuration, the in-wheel motor can realize two shift states, a first shift state and a second shift state. In the first speed change state, the first motor and the second motor operate, and the clutch device is in an engaged state. In the first speed change state, the in-wheel motor has a part of the rotational force returned from the second carrier to the first ring gear, and the rotational force transmitted to the first ring gear is transmitted to the second sun gear via the first sun gear. It is transmitted. That is, in this in-wheel motor, the rotational force circulates. With such a structure, the in-wheel motor can realize a larger gear ratio. That is, the in-wheel motor can transmit a rotational force larger than the rotational force output by the first motor to the wheel in the first speed change state.

  In the second speed change state, the first motor and the second motor operate, and the clutch device is in a non-engagement state. The in-wheel motor can continuously change the gear ratio by changing the angular speed of the second motor in the second speed change state. By doing in this way, this in-wheel motor can reduce the difference between the angular velocity of the first motor and the angular velocity of the second ring gear serving as the output shaft, so that the friction loss can be reduced, resulting in the loss of energy. Can be reduced.

  The in-wheel motor has a speed reduction mechanism including a third sun gear, a fourth pinion gear, a third carrier, and a third ring gear. Since this in-wheel motor can amplify the rotational force of the first motor and the second motor by the speed reduction mechanism, the rotational force required for the first motor and the second motor can be reduced. As a result, since the first motor and the second motor can be reduced in size and weight, the in-wheel motor can be reduced in size and weight.

  In the present invention, the clutch device includes a first member, a second member that can rotate with respect to the first member, and when the rotational force in the first direction acts on the second member, the first member and the second member. A rotational force is transmitted between the first member and the second member when a rotational force in a second direction opposite to the first direction acts on the second member. It is preferable that the one-way clutch device includes an engaging member that does not.

  The one-way clutch device can switch between the engaged state and the non-engaged state by switching the direction of the rotational force acting on the second member. Therefore, the one-way clutch device does not require a mechanism for moving the piston or an electromagnetic actuator. Thereby, the in-wheel motor which concerns on this invention can reduce a number of parts, and can miniaturize itself (clutch apparatus). In addition, the one-way clutch device does not require a mechanism for moving the piston or energy for operating the electromagnetic actuator.

  In the present invention, the first motor may be arranged to rotate in a direction to advance an electric vehicle on which the in-wheel motor is mounted and to engage when the second motor is not driven. preferable. In this way, the first shift state can be a so-called low gear, and the second shift state can be a so-called high gear.

  In the present invention, the clutch device is preferably a sprag type one-way clutch. Since the sprag type one-way clutch uses a sprag as a friction engagement member, more sprags can be arranged in the clutch device than the number of cams having a bottom surface similar to a circle. As a result, the torque capacity of the clutch device can be made larger than the torque capacity of the cam clutch device having the same mounting dimensions as the clutch device.

  The present invention can provide an in-wheel motor capable of reducing energy loss.

FIG. 1 is a diagram illustrating a configuration of an electric vehicle driving apparatus according to the present embodiment. FIG. 2 is an explanatory diagram illustrating a path through which the rotational force is transmitted when the electric vehicle drive device according to the present embodiment is in the first speed change state. FIG. 3 is an explanatory diagram showing a path through which the rotational force is transmitted when the electric vehicle drive device according to the present embodiment is in the second speed change state. FIG. 4 is an explanatory view showing the clutch device of the present embodiment. FIG. 5 is an explanatory view showing an enlarged cam of the clutch device of the first embodiment. FIG. 6 is a diagram showing an internal structure of the electric vehicle drive device according to the present embodiment. FIG. 7A is a perspective view of the first magnetic pattern ring and the second magnetic pattern ring. 7-2 is a cross-sectional view taken along line AA of FIG. 7-2. FIG. 7C is a perspective view illustrating the arrangement of the magnetic detectors. FIG. 8 is a diagram showing the relationship between the rotational force (torque) required for the motor that drives the vehicle and the angular velocity (rotational speed). FIG. 9 is an explanatory diagram showing a configuration of an electric vehicle drive device according to a modification of the present embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those that are equivalent. Furthermore, the constituent elements described below can be appropriately combined. In addition, various omissions, substitutions, or changes of components can be made without departing from the scope of the present invention.

  FIG. 1 is a diagram illustrating a configuration of an electric vehicle driving apparatus according to the present embodiment. The electric vehicle drive device 10 that is an in-wheel motor includes a casing G, a first motor 11, a second motor 12, a speed change mechanism 13, a speed reduction mechanism 40, and a wheel bearing 50. The casing G houses the first motor 11, the second motor 12, the speed change mechanism 13, and the speed reduction mechanism 40.

  The first motor 11 can output the first rotational force TA. The second motor 12 can output the second rotational force TB. The speed change mechanism 13 is connected to the first motor 11. With such a structure, when the first motor 11 is operated, the transmission mechanism 13 receives (inputs) the first rotational force TA from the first motor 11. The transmission mechanism 13 is connected to the second motor 12. With this structure, the transmission mechanism 13 is transmitted (inputted) with the second rotational force TB when the second motor 12 is operated. The operation of the motor here means that electric power is supplied to the first motor 11 (second motor 12) and the input / output shaft of the first motor 11 (second motor 12) rotates.

  The transmission mechanism 13 can change the reduction ratio (ratio ωi / ωo between the input rotational speed ωi and the output rotational speed ωo to the transmission mechanism 13). The speed change mechanism 13 includes a first planetary gear mechanism 20, a second planetary gear mechanism 30, and a clutch device 60. The first planetary gear mechanism 20 is a single pinion type planetary gear mechanism. The first planetary gear mechanism 20 includes a first sun gear 21, a first pinion gear 22, a first carrier 23, and a first ring gear 24. The second planetary gear mechanism 30 is a double pinion planetary gear mechanism. The second planetary gear mechanism 30 includes a second sun gear 31, a second pinion gear 32a, a third pinion gear 32b, a second carrier 33, and a second ring gear 34.

  The first sun gear 21 is supported in the casing G so as to be able to rotate (spin) about the rotation axis R. The first sun gear 21 is connected to the first motor 11. With such a structure, the first sun gear 21 receives the first rotational force TA when the first motor 11 is operated. The first sun gear 21 rotates about the rotation axis R when the first motor 11 is operated. The first pinion gear 22 meshes with the first sun gear 21. The first carrier 23 holds the first pinion gear 22 so that the first pinion gear 22 can rotate (rotate) about the first pinion rotation axis Rp1. The first pinion rotation axis Rp1 is, for example, parallel to the rotation axis R.

  The first carrier 23 is supported in the casing G so that it can rotate (rotate) about the rotation axis R. With such a structure, the first carrier 23 holds the first pinion gear 22 so that the first pinion gear 22 can revolve around the first sun gear 21, that is, around the rotation axis R. The first ring gear 24 can rotate (spin) about the rotation axis R. The first ring gear 24 meshes with the first pinion gear 22. The first ring gear 24 is connected to the second motor 12. With this structure, the first ring gear 24 transmits the second rotational force TB when the second motor 12 is operated. The first ring gear 24 rotates (rotates) about the rotation axis R when the second motor 12 is operated.

  The clutch device 60 is disposed between the casing G and the first carrier 23. The clutch device 60 can regulate the rotation of the first carrier 23. Specifically, the clutch device 60 can switch between restricting (braking) the rotation of the first carrier 23 around the rotation axis R and allowing the rotation. Hereinafter, in the clutch device 60, a state where the rotation is restricted (braking) is referred to as an engaged state, and a state where the rotation is allowed is referred to as a non-engaged state. Details of the clutch device 60 will be described later.

  Thus, the first carrier 23 can be engaged with and separated from the casing G by the clutch device 60. That is, the clutch device 60 can make the first carrier 23 rotatable with respect to the casing G, or make the first carrier 23 non-rotatable with respect to the casing G.

  The second sun gear 31 is supported in the casing G so as to rotate (spin) around the rotation axis R. The second sun gear 31 is connected to the first motor 11 via the first sun gear 21. Specifically, the first sun gear 21 and the second sun gear 31 are formed integrally with the sun gear shaft 14 so that each can rotate on the same axis (rotation axis R). The sun gear shaft 14 is connected to the first motor 11. With such a structure, the second sun gear 31 rotates around the rotation axis R when the second motor 12 is operated.

  The second pinion gear 32 a meshes with the second sun gear 31. The third pinion gear 32b meshes with the second pinion gear 32a. The second carrier 33 holds the second pinion gear 32a so that the second pinion gear 32a can rotate (spin) about the second pinion rotation axis Rp2. The second carrier 33 holds the third pinion gear 32b so that the third pinion gear 32b can rotate (rotate) about the third pinion rotation axis Rp3. The second pinion rotation axis Rp2 and the third pinion rotation axis Rp3 are parallel to the rotation axis R, for example.

  The second carrier 33 is supported in the casing G so that it can rotate (rotate) about the rotation axis R. With such a structure, the second carrier 33 has the second pinion gear 32a and the second pinion gear 32a and the third pinion gear 32b so that the second pinion gear 32a and the third pinion gear 32b can revolve around the second sun gear 31, that is, around the rotation axis R. The three pinion gear 32b is held. The second carrier 33 is connected to the first ring gear 24. With such a structure, the second carrier 33 rotates (spins) about the rotation axis R when the first ring gear 24 rotates (spins). The second ring gear 34 can rotate (rotate) about the rotation axis R. The second ring gear 34 meshes with the third pinion gear 32b. The second ring gear 34 is connected to the input / output shaft (transmission mechanism input / output shaft) 15 of the transmission mechanism 13. With this structure, when the second ring gear 34 rotates (spins), the transmission mechanism input / output shaft 15 rotates.

  Deceleration mechanism 40 is arranged between transmission mechanism 13 and wheels H of the electric vehicle. The reduction mechanism 40 decelerates the rotational speed of the transmission mechanism input / output shaft 15 and outputs it to the input / output shaft (deceleration mechanism input / output shaft) 16. The speed reduction mechanism input / output shaft 16 is connected to the wheel H of the electric vehicle, and transmits power between the speed reduction mechanism 40 and the wheel H. With such a structure, the power generated by at least one of the first motor 11 and the second motor 12 is transmitted to the wheel H via the speed change mechanism 13 and the speed reduction mechanism 40 to drive it. The input from the wheel H is transmitted to at least one of the first motor 11 and the second motor 12 via the speed reduction mechanism 40 and the speed change mechanism 13. In this case, at least one of the first motor 11 and the second motor 12 can be driven by the wheel H to generate electric power (regeneration).

  The speed reduction mechanism 40 includes a third sun gear 41, a fourth pinion gear 42, a third carrier 43, and a third ring gear 44. The transmission mechanism input / output shaft 15 is attached to the third sun gear 41. With such a structure, the third sun gear 41 and the second ring gear 34 of the transmission mechanism 13 are connected via the transmission mechanism input / output shaft 15. The fourth pinion gear 42 meshes with the third sun gear 41. The third carrier 43 has a fourth pinion gear 42 so that the fourth pinion gear 42 can rotate about the fourth pinion rotation axis Rp4 and so that the fourth pinion gear 42 can revolve about the third sun gear 41. Hold. The third ring gear 44 meshes with the fourth pinion gear 42 and is fixed to the stationary system (the casing G in the present embodiment). The third carrier 43 is connected to the wheel H via the speed reduction mechanism input / output shaft 16. The third carrier 43 is rotatably supported by the wheel bearing 50.

  The electric vehicle drive device 10 drives the wheels H by interposing a speed reduction mechanism 40 between the speed change mechanism 13 and the wheels H to reduce the rotational speed of the transmission purchase output shaft 15 of the speed change mechanism 13. For this reason, even if the 1st motor 11 and the 2nd motor 12 have a small maximum rotational force, the driving force required for an electric vehicle can be obtained. As a result, the drive currents of the first motor 11 and the second motor 12 can be reduced, and they can be reduced in size and weight. And the manufacturing cost reduction and weight reduction of the electric vehicle drive device 10 are realizable.

  The control device 1 controls the operation of the electric vehicle drive device 10. More specifically, the control device 1 controls the rotation speed, rotation direction, and output of the first motor 11 and the second motor 12. The control device 1 is, for example, a microcomputer. Next, the transmission path of the rotational force in the electric vehicle drive device 10 will be described.

  FIG. 2 is an explanatory diagram illustrating a path through which the rotational force is transmitted when the electric vehicle drive device according to the present embodiment is in the first speed change state. The electric vehicle drive device 10 can realize two shift states, a first shift state and a second shift state. First, the case where the electric vehicle drive device 10 realizes the first shift state will be described.

  The first speed change state is a so-called low gear state, and a large reduction ratio can be obtained. That is, the torque of the transmission mechanism input / output shaft 15 can be increased. The first speed change state is mainly used when the electric vehicle requires a large driving force when traveling, for example, when starting a slope or climbing (when climbing a slope). In the first speed change state, both the first motor 11 and the second motor 12 operate, but the magnitude of the generated torque is equal and the direction of the torque is opposite. The power of the first motor 11 is input to the first sun gear 23, and the power of the second motor 12 is input to the first ring gear 24. In the first speed change state, the clutch device 60 is in an engaged state. That is, in the first speed change state, the first pinion gear 22 cannot rotate with respect to the casing G.

  In the first speed change state, the rotational force output by the first motor 11 is defined as a first rotational force T1, and the rotational force output by the second motor 12 is defined as a second rotational force T5. The respective rotational forces of the first rotational force T1, the circulating rotational force T3, the combined rotational force T2, the first distributed rotational force T6 and the second distributed rotational force T4 shown in FIG. Nm.

  The first rotational force T <b> 1 output from the first motor 11 is input to the first sun gear 21. Then, the first rotational force T1 merges with the circulating rotational force T3 at the first sun gear 21 to become a combined rotational force T2. The combined rotational force T2 is output from the first sun gear 21. The circulating rotational force T3 is a rotational force transmitted from the first ring gear 24 to the first sun gear 21. Details of the circulating rotational force T3 will be described later.

  The first sun gear 21 and the second sun gear 31 are connected by the sun gear shaft 14. Therefore, in the first speed change state, the first rotational force T1 and the circulating rotational force T3 are combined, and the combined rotational force T2 output from the first sun gear 21 is transmitted to the sun gear shaft 14 via the sun gear shaft 14. . The combined rotational force T2 is amplified by the second planetary gear mechanism 30. The combined rotational force T2 is distributed by the second planetary gear mechanism 30 to the first distributed rotational force T6 and the second distributed rotational force T4. The first distributed rotational force T6 is a rotational force obtained by distributing and amplifying the combined rotational force T2 to the second ring gear 34, and is output from the transmission mechanism input / output shaft 15. The second distributed rotational force T4 is a rotational force obtained by distributing and amplifying the combined rotational force T2 to the second carrier 33.

  The first distributed rotational force T6 is output from the speed change mechanism input / output shaft 15 to the speed reduction mechanism 40. Then, the first distributed rotational force T6 is amplified by the speed reduction mechanism 40 and is output to the wheel H via the speed reduction mechanism input / output shaft 16 shown in FIG. 1 to drive it. As a result, the electric vehicle travels.

  Since the second carrier 33 and the first ring gear 24 rotate together, the second distributed rotational force T4 distributed to the second carrier 33 becomes the circulating rotational force of the first ring gear 24. The second distributed rotational force T4 is combined with the second rotational force T5 of the second motor 12 by the first ring gear 24 and travels toward the first planetary gear mechanism 20. The second rotational force T5, that is, the direction of the rotational force of the second motor 12 is opposite to the direction of the rotational force of the first motor 11.

  The second distributed rotational force T4 and the second rotational force T5 in the first ring gear 24 returned to the first planetary gear mechanism 20 are reduced in magnitude by the first planetary gear mechanism 20, and the direction of the force is changed. By being reversely rotated, a circulating rotational force T3 in the first sun gear 21 is obtained. In this manner, since power (rotational force) is circulated between the first planetary gear mechanism 20 and the second planetary gear mechanism 30, the speed change mechanism 13 can increase the reduction ratio. That is, the electric vehicle drive device 10 can generate a large torque when in the first shift state. Next, an example of values of the combined rotational force T2, the circulating rotational force T3, the second distributed rotational force T4, and the first distributed rotational force T6 will be described.

  The number of teeth of the second sun gear 31 is Z1, the number of teeth of the second ring gear 34 is Z4, the number of teeth of the first sun gear 21 is Z5, and the number of teeth of the first ring gear 24 is Z7. From the formula (1) to the formula (4), the rotational force acting on each part of the electric vehicle drive device 10 (the combined rotational force T2, the circulating rotational force T3, the second distributed rotational force T4 and the first distributed rotational force shown in FIG. T6). In addition, what becomes a negative value in the following formulas (1) to (4) is a rotational force in a direction opposite to the first rotational force T1.

  As an example, the number of teeth Z1 is 47, the number of teeth Z4 is 97, the number of teeth Z5 is 24, and the number of teeth Z7 is 76. Further, the first rotational force T1 is set to 50 Nm, and the second rotational force T5 is set to 50 Nm. Then, the combined rotational force T2 is 99.1 Nm, the circulating rotational force T3 is 49.1 Nm, the second distributed rotational force T4 is −105.4 Nm, and the first distributed rotational force T6 is 204.5 Nm. Thus, the electric vehicle drive apparatus 10 can amplify the 1st rotational force T1 which the 1st motor 11 outputs as an example, and can output it to the wheel H about 4 times. Next, the case where the electric vehicle drive device 10 realizes the second shift state will be described.

  FIG. 3 is an explanatory diagram showing a path through which the rotational force is transmitted when the electric vehicle drive device according to the present embodiment is in the second speed change state. The second speed change state is a so-called high gear state, and the reduction ratio can be made small. That is, the torque of the transmission mechanism input / output shaft 15 is reduced, but the friction loss of the transmission mechanism 13 can be reduced. In the second speed change state, both the first motor 11 and the second motor 12 operate. The magnitude of torque generated by the first motor 11 and the second motor 12 is equal to the direction of the torque. In the second speed change state, the rotational force output by the first motor 11 is defined as a first rotational force T7, and the rotational force output by the second motor 12 is defined as a second rotational force T8.

  In the second speed change state, the power of the first motor 11 is input to the first sun gear 23, and the power of the second motor 12 is input to the first ring gear 24. In the second speed change state, the clutch device 60 is in a disengaged state. That is, in the first speed change state, the first pinion gear 22 can rotate with respect to the casing G. As a result, in the second speed change state, the circulation of the rotational force between the first planetary gear mechanism 20 and the second planetary gear mechanism 30 is interrupted. In the second speed change state, the first carrier 23 can freely revolve (rotate), so that the first sun gear 21 and the first ring gear 24 can relatively freely rotate (spin). The combined rotational force T9 shown in FIG. 3 indicates torque output from the transmission mechanism input / output shaft 15 and transmitted to the speed reduction mechanism 40, and its unit is Nm.

  In the second speed change state, the ratio between the first rotational force T7 and the second rotational force T8 is determined by the ratio between the number of teeth Z1 of the second sun gear 31 and the number of teeth Z4 of the second ring gear 34. The first rotational force T7 merges with the second rotational force T8 at the second carrier 33. As a result, the combined rotational force T9 is transmitted to the second ring gear 34. The first rotational force T7, the second rotational force T8, and the combined rotational force T9 satisfy the following formula (5).

  The angular speed (rotational speed) of the transmission mechanism input / output shaft 15 is determined by the angular speed of the second sun gear 31 driven by the first motor 11 and the angular speed of the second carrier 33 driven by the second motor 12. Therefore, even if the angular velocity of the transmission mechanism input / output shaft 15 is constant, the combination of the angular velocity of the first motor 11 and the angular velocity of the second motor 12 can be changed.

  As described above, since the combination of the angular speed of the transmission mechanism input / output shaft 15, the angular speed of the first motor 11, and the angular speed of the second motor 12 is not uniquely determined, the first shift state to the second shift state described above, or The second shift state can be continuously shifted to the first shift state. Therefore, when the control device 1 continuously and smoothly controls the angular speed of the first motor 11, the angular speed of the second motor 12, and the rotational force, the speed change mechanism 13 is switched between the first speed change state and the second speed change state. Even when the state changes, so-called shift shock can be reduced.

  In the transmission mechanism 13, the first sun gear 21 and the first ring gear 24 rotate (spin) in the same direction, so that the second sun gear 31 and the second carrier 33 also rotate (spin) in the same direction. When the angular velocity of the second sun gear 31 is constant, the angular velocity of the second ring gear 34 decreases as the angular velocity of the second carrier 33 increases. Further, the angular velocity of the second ring gear 34 increases as the angular velocity of the second carrier 33 decreases. As described above, the angular velocity of the second ring gear 34 continuously changes depending on the angular velocity of the second sun gear 31 and the angular velocity of the second carrier 33. That is, the electric vehicle drive device 10 can continuously change the gear ratio by changing the angular velocity of the second rotational force T8 output from the second motor 12.

  Further, when the electric vehicle drive device 10 tries to keep the angular velocity of the second ring gear 34 constant, the electric vehicle driving device 10 outputs the angular velocity of the first rotational force T7 output by the first motor 11 and the second velocity output by the second motor 12. There are a plurality of combinations with the angular velocity of the rotational force T8. That is, even if the angular velocity of the first rotational force T7 output from the first motor 11 changes due to the change in the angular velocity of the second rotational force T8 output from the second motor 12, the angular velocity of the second ring gear 34 is changed. Can be kept constant. For this reason, the electric vehicle drive device 10 can reduce the amount of change in the angular velocity of the second ring gear 34 when switching from the first shift state to the second shift state. As a result, the electric vehicle drive device 10 can reduce the shift shock.

  Next, the second rotational force T8 output from the second motor 12 will be described. The 2nd motor 12 needs to output the rotational force more than 2nd rotational force T8 which satisfy | fills Formula (6). In the formula (6), 1- (Z4 / Z1) represents a rotational force ratio between the second sun gear 31 and the second ring gear 34.

  Therefore, in order to adjust the rotational force and angular velocity of the second ring gear 34 when the first motor 11 rotates arbitrarily, the first rotational force TA, the second rotational force TB, the number of teeth Z1, the teeth The number Z4 may satisfy the following formula (7). The first rotational force TA is a rotational force at an arbitrary angular velocity of the first motor 11, and the second rotational force TB is a rotational force at an arbitrary angular velocity of the second motor 12.

  Next, the clutch device 60 will be described. The clutch device 60 is, for example, a one-way clutch device. The one-way clutch device transmits only the rotational force in the first direction, and does not transmit the rotational force in the second direction that is opposite to the first direction. That is, the one-way clutch device is engaged when the first carrier 23 shown in FIGS. 1 to 3 tries to rotate in the first direction, and is not used when the first carrier 23 tries to rotate in the second direction. The engaged state is established. The one-way clutch device is, for example, a cam clutch device or a roller clutch device. Hereinafter, the configuration of the clutch device 60 will be described assuming that the clutch device 60 is a cam clutch device.

  FIG. 4 is an explanatory view showing the clutch device of the present embodiment. FIG. 5 is an explanatory view showing an enlarged cam of the clutch device of the first embodiment. As shown in FIG. 4, the clutch device 60 includes an inner ring 61 as a second member, an outer ring 62 as a first member, and a cam 63 as an engaging member. The inner ring 61 may function as the first member, and the outer ring 62 may function as the second member. The inner ring 61 and the outer ring 62 are cylindrical members. The inner ring 61 is disposed inside the outer ring 62. One of the inner ring 61 and the outer ring 62 is connected to the first carrier 23, and the other is connected to the casing G. In the present embodiment, the inner ring 61 is connected to the first carrier 23 and the outer ring 62 is connected to the casing G. The cam 63 is a substantially cylindrical rod-shaped member. However, the cross-sectional shape of the cam 63 cut by a virtual plane orthogonal to the central axis of the rod-shaped member is not a perfect circle but a distorted shape. A plurality of cams 63 are provided along the circumferential direction of the inner ring 61 and the outer ring 62 between the outer peripheral part of the inner ring 61 and the inner peripheral part of the outer ring 62.

  As shown in FIG. 5, the clutch device 60 includes a wire gauge 64 and a garter spring 65. The wire gauge 64 is an elastic member. The wire gauge 64 is arranged so that the plurality of cams 63 are not dispersed. The garter spring 65 applies a force to the cam 63 so that the cam 63 always contacts the inner ring 61 and the outer ring 62. Thereby, when a rotational force acts on the inner ring 61 or the outer ring 62, the cam 63 can quickly mesh with the inner ring 61 and the outer ring 62. Therefore, the clutch device 60 can reduce the time required for switching from the disengaged state to the engaged state. In the disengaged state, no force is transmitted between the inner ring 61 and the outer ring 62. In the engaged state, force is transmitted between the inner ring 61 and the outer ring 62.

  In the clutch device 60, when a rotational force in the first direction acts on the inner ring 61, the cam 63 meshes with the inner ring 61 and the outer ring 62. Thereby, a rotational force is transmitted between the inner ring 61 and the outer ring 62, and the first carrier 23 receives a reaction force from the casing G. As a result, the clutch device 60 can regulate the rotation of the first carrier 23. Further, in the clutch device 60, when the rotational force in the second direction acts on the inner ring 61, the cam 63 does not mesh with the inner ring 61 and the outer ring 62. Thereby, the rotational force is not transmitted between the inner ring 61 and the outer ring 62, and the first carrier 23 does not receive a reaction force from the casing G. For this reason, the clutch device 60 does not restrict the rotation of the first carrier 23. In this way, the clutch device 60 realizes a function as a one-way clutch device.

  In the case of this embodiment, the clutch device 60 is in the first speed change state, that is, the state in which the first motor 11 and the second motor 12 are operating, and the first motor 11 has a rotational force so as to advance the electric vehicle. When the inner ring 61 rotates in the direction in which the first carrier 23 shown in FIG. 1 rotates (spins), the engagement state is established. That is, in the first direction described above, the inner ring 41 as the second member is output when the first motor 11 outputs a rotational force so as to advance the electric vehicle and the second motor 12 is not operated (driven). Is the direction of rotation. In this state, when the second motor 12 rotates in a direction opposite to the rotation direction of the first motor 11 and outputs a rotation force in the direction opposite to the rotation force of the first motor 11, the speed change mechanism 13. Is in the first shift state. As described above, the clutch device 60 is disposed in a direction to be engaged when the first motor 11 rotates in a direction for moving the electric vehicle forward and the second motor 12 is not driven.

  In addition, the second motor 12 operates in a state where the first motor 11 outputs a rotational force so as to move the electric vehicle forward, and rotates in the same direction as the rotation direction of the first motor 11. When the rotational force in the same direction as the rotational force of the motor 11 is output, the rotational direction of the second carrier 33 is reversed. As a result, when the clutch device 60 is in the second speed change state, that is, the first motor 11 and the second motor 12 are operated to output the rotational force in the same direction, and the first motor is moved forward. When the motor 11 and the second motor 12 output a rotational force, they are disengaged. Thus, the clutch device 60 can passively switch between the engaged state and the non-engaged state depending on the direction of the rotational force of the first motor 11 and the direction of the rotational force of the second motor 12.

  The clutch device 60 may be a roller clutch device. However, the cam clutch device has a larger rotational force (torque) capacity than the roller clutch device. That is, the magnitude of the force that can be transmitted between the inner ring 61 and the outer ring 62 is greater in the cam clutch device than in the roller clutch device. For this reason, the clutch device 60 can transmit a larger rotational force when it is a cam clutch device. Further, when the clutch device 60 is a cam clutch device, idling friction when the cam 63 is separated from the inner ring 61 and the outer ring 62 can be made smaller than that of the roller clutch device. For this reason, the friction loss of the whole electric vehicle drive device 10 can be reduced, and efficiency can be improved. The first shift state and the second shift state are switched by the control device 1 controlling the rotational force and the rotation direction of the first motor 11 and the second motor 12.

  In the present embodiment, the electric vehicle drive device 10 is configured such that the magnitude of the rotational force between the first motor 11 and the second motor 12 is equal and the direction of the rotational force is reversed. Realized the shift state. However, the electric vehicle drive device 10 can also realize the first shift state by operating only the first motor 11 without operating the second motor 12. In this case, the control device 1 realizes the first shift state by stopping the second motor 12 and operating only the first motor 11.

  The clutch device 60 may be a sprag type one-way clutch device. Since the sprag type one-way clutch uses a sprag as a friction engagement member, a larger number of sprags can be disposed in the clutch device 60 than the number of cams having a bottom surface similar to a circle. As a result, the torque capacity of the clutch device 60 can be made larger than the torque capacity of the cam clutch device having the same mounting dimensions as the clutch device 60. Since the torque capacity of the clutch device 60 can be increased, the maximum value of the first distributed rotational force T6 output to the wheels H can be increased.

  Further, the clutch device 60 is not a one-way clutch device, but is a type of engaging two rotating members by moving a piston in a cylinder with a working fluid or engaging two rotating members by an electromagnetic actuator. A clutch device may be used. However, such a clutch device requires a mechanism for moving the piston or requires electric power for operating the electromagnetic actuator. However, if the clutch device 60 is a one-way clutch device, it does not require a mechanism for moving the piston, and does not require electric power for operating the electromagnetic actuator. If the clutch device 60 is a one-way clutch device, the direction of the rotational force acting on the inner ring 61 or the outer ring 62 (in this embodiment, the inner ring 61) can be switched to switch between the engaged state and the non-engaged state. Therefore, if the clutch device 60 is a one-way clutch device, the number of parts can be reduced, and the size of the clutch device 60 (the clutch device 60) can be reduced. Next, an example of the structure of the electric vehicle drive device 10 will be described.

  FIG. 6 is a diagram showing an internal structure of the electric vehicle drive device according to the present embodiment. In the following description, overlapping description of the above-described components is omitted, and the same reference numerals are used in the drawings. As shown in FIG. 7, the casing G includes a first casing G1, a second casing G2, a third casing G3, and a fourth casing G4. The first casing G1, the second casing G2, and the fourth casing G4 are cylindrical members. The second casing G2 is provided closer to the wheel H than the first casing G1. The first casing G1 and the second casing G2 are fastened with, for example, a plurality of bolts.

  The third casing G3 is provided at the opening end opposite to the second casing G2 of the two opening ends of the first casing G1, that is, the opening end of the first casing G1 on the vehicle body side of the electric vehicle. The first casing G1 and the third casing G3 are fastened by a plurality of bolts 52, for example. In this way, the third casing G3 closes the opening of the first casing G1. The fourth casing G4 is provided inside the first casing G1. The first casing G1 and the fourth casing G4 are fastened with, for example, a plurality of bolts.

  As shown in FIG. 6, the first motor 11 includes a first stator core 11a, a first coil 11b, a first rotor 11c, a first magnetic pattern ring 11d, and a first motor output shaft 11e. The first stator core 11a is a cylindrical member. As shown in FIG. 6, the first stator core 11a is fitted into the first casing G1, and is positioned (fixed) by being sandwiched between the first casing G1 and the third casing G3. The first coil 11b is provided at a plurality of locations of the first stator core 11a. The first coil 11b is wound around the first stator core 11a via an insulator.

  The first rotor 11c is disposed on the radially inner side of the first stator core 11a. The first rotor 11c includes a first rotor core 11c1 and a first magnet 11c2. The first rotor core 11c1 is a cylindrical member. A plurality of first magnets 11c2 are provided inside or on the outer periphery of the first rotor core 11c1. The first motor output shaft 11e is a rod-shaped member. The first motor output shaft 11e is connected to the first rotor core 11c1. The first magnetic pattern ring 11d is provided on the first rotor core 11c1 and rotates coaxially with the first rotor core 11c1. The first magnetic pattern ring 11d is used when detecting the rotation angle of the first rotor core 11c1.

  The second motor 12 includes a second stator core 12a, a second coil 12b, a second rotor 12c, and a second magnetic pattern ring 12d. The second stator core 12a is a cylindrical member. The second stator core 12a is sandwiched and positioned (fixed) between the first casing G1 and the second casing G2. The second coil 12b is provided at a plurality of locations of the second stator core 12a. The second coil 12b is wound around the second stator core 12a via an insulator.

  The second rotor 12c is provided on the radially inner side of the second stator core 12a. The second rotor 12c is supported by the fourth casing G4 so as to be able to rotate around the rotation axis R together with the clutch device 60. The second rotor 12c includes a second rotor core 12c1 and a second magnet 12c2. The second rotor core 12c1 is a cylindrical member. A plurality of second magnets 12c2 are provided inside or on the outer periphery of the second rotor core 12c1. The second magnetic pattern ring 12d is provided on the second rotor core 12c1 and rotates coaxially with the second rotor core 12c1. The second magnetic pattern ring 12d is used when detecting the rotation angle of the second rotor core 12c1.

  As illustrated in FIG. 6, the speed reduction mechanism 40 is fastened and attached to the second casing G <b> 2 with a plurality of bolts 54, for example. In the present embodiment, the third ring gear 44 included in the speed reduction mechanism 40 is attached to the second casing G2. An outer ring 45 is attached to one end of the third carrier 43 of the speed reduction mechanism 40. A rolling element of the wheel bearing 50 is interposed between the outer ring 45 and the third ring gear 44. With such a structure, the third carrier 43 is rotatably supported on the outer peripheral portion of the third ring gear 44 via the outer ring 45.

  The wheel Hw of the wheel H is attached to the third carrier 43. The wheel Hw is fastened to a surface orthogonal to the rotation axis of the third carrier 43 by the stud bolt 51B and the nut 51N. A tire Ht is attached to the wheel Hw. The wheel H of the electric vehicle includes a wheel Hw and a tire Ht. In this example, the wheel H is directly attached to the third carrier 43. For this reason, the third carrier 43 also serves as the speed reduction mechanism input / output shaft 16 shown in FIG.

  The suspension device attachment portion 53 is provided in the second casing G2. Specifically, the suspension device attachment portion 53 is provided in portions of the second casing G2 that are on the upper side and the lower side in the vertical direction when the electric vehicle drive device 10 is attached to the vehicle body of the electric vehicle. The vertically upper suspension device mounting portion 53 includes an upper knuckle 53Nu, and the vertically lower suspension device mounting portion 53 includes a lower knuckle 53Nb. A suspension arm is attached to the upper knuckle 53Nu and the lower knuckle 53Nb, and the electric vehicle driving apparatus 10 is supported by the vehicle body of the electric vehicle.

  The first motor output shaft 11e and the sun gear shaft 14 are connected by a first fitting portion 56A. With such a structure, power is transmitted between the first motor 11 and the sun gear shaft 14. 56 A of 1st fitting parts are formed in the edge part in the 1st motor 11 side of the sun gear shaft 14 and the spline formed in the internal peripheral surface of the 1st motor output shaft 11e, for example, and it fits with the said spline. It consists of splines. With such a structure, thermal elongation or the like between the first motor output shaft 11e and the sun gear shaft 14 in the direction of the rotation axis R is absorbed.

  The transmission input / output shaft 15 connects the second ring gear 34 included in the transmission mechanism 13 and the shaft (third sun gear shaft) 41 </ b> S of the third sun gear 41 included in the speed reduction mechanism 40. With such a structure, power is transmitted between the second planetary gear mechanism 30 of the speed change mechanism 13 and the third sun gear shaft 41S of the speed reduction mechanism 40. The transmission input / output shaft 15 and the third sun gear shaft 41S are connected by a second fitting portion 56B. The second fitting portion 56B is formed at, for example, a spline formed on the inner peripheral surface of the transmission input / output shaft 15 and an end portion of the third sun gear shaft 41S on the second motor 12 side, and is fitted with the spline. Consists of splines that match. With such a structure, thermal expansion or the like between the transmission input / output shaft 15 and the third sun gear shaft 41S in the direction of the rotation axis R is absorbed.

  With the above-described structure, the electric vehicle drive device 10 holds the wheel H and transmits the rotational force output from the first motor 11 and the second motor 12 to the wheel H, thereby causing the electric vehicle to travel. Can do. In the present embodiment, the first motor 11, the second motor 12, the first sun gear 21, the first carrier 23, the first ring gear 24, the second sun gear 31, the second carrier 33, The second ring gear 34, the third sun gear 41, the third carrier 43, and the third ring gear 44 are all arranged coaxially. However, in the electric vehicle drive device 10, these components are not necessarily coaxial. It does not have to be placed on top. Next, a structure for detecting the angular velocity (rotational speed) of the first motor 11 and the second motor 12 will be described.

  The first magnetic pattern ring 11d and the second magnetic pattern ring 12d are arranged to face each other with a partition wall G1W of the casing G1 interposed between the first motor 11 and the second motor 12 interposed therebetween. That is, the first magnetic pattern ring 11d and the second magnetic pattern ring 12d are opposed to the partition wall G1W, respectively.

  FIG. 7A is a perspective view of the first magnetic pattern ring and the second magnetic pattern ring. 7-2 is a cross-sectional view taken along line AA of FIG. 7-2. FIG. 7C is a perspective view illustrating the arrangement of the magnetic detectors. As illustrated in FIG. 7A, the first magnetic pattern ring 11d and the second magnetic pattern ring 12d are annular members, and have an opening MH at the center. The sun gear shaft 14 shown in FIG. 6 passes through the opening MH.

  The electric vehicle drive device 10 shown in FIGS. 1 and 6 includes a first planetary gear mechanism 20 and a second planetary gear mechanism that are radially inward of the first rotor 11 c of the first motor 11 and the second rotor 12 c of the second motor 12. 30 is arranged. For this reason, it is difficult to use a small-diameter resolver as the rotation angle detection sensor particularly for the motor on the wheel H side (second motor 12). Use of a large-diameter resolver is not preferable because the mass increases.

  As shown in FIG. 7-2, the first magnetic pattern ring 11d and the second magnetic pattern ring 12d are obtained by forming a thin magnet layer MP on the surface of an annular thin metal plate BM. The metal plate BM is, for example, an aluminum alloy. The magnet layer MP is, for example, a resin such as plastic or rubber mixed with magnetic powder. A magnetic pattern is magnetized on the magnet layer MP. With such a structure, even if the first magnetic pattern ring 11d and the second magnetic pattern ring 12d have a large diameter, they can be significantly reduced in weight compared to the resolver.

  One magnetic detector (magnetic pickup sensor) 2 shown in FIG. 7C is prepared for each of the first magnetic pattern ring 11d and the second magnetic pattern ring 12d, and the inside of the first casing G1 of the casing G. Attached to. The magnetic detector 2 is disposed on both sides of the partition wall G1W of the first casing G1 and outside the through hole GH of the partition wall G1W. The sun gear shaft 14 shown in FIG. 6 passes through the through hole GH. With such a structure, each magnetic detector 2 is disposed to face the first magnetic pattern ring 11d and the second magnetic pattern ring 12d. Although FIG. 7-3 shows only one magnetic detector 2, another magnetic detector 2 is disposed on the back side of the partition wall G1W.

  Each magnetic detector 2 detects the magnetic flux between the first magnetic pattern ring 11d and the second magnetic pattern ring 12d, and calculates the absolute angle between the first rotor 11c and the second rotor 12c of the first motor 11. . For example, the first magnetic pattern ring 11d and the second magnetic pattern ring 12d are magnetized so that the magnetic flux density changes sinusoidally. In the first magnetic pattern ring 11d and the second magnetic pattern ring 12d, the number of sine waves in one turn is equal to the number of pole pairs between the first motor 11 and the second motor, respectively. That is, one cycle of the sine wave pattern corresponds to one pole pair.

  In the magnetic detector 2, for example, two linear Hall sensors are provided, and each linear Hall sensor is disposed at a position that is 90 degrees out of phase with respect to one cycle of the sine wave pattern. . By detecting and calculating the magnetic flux density of the first magnetic pattern ring 11d or the second magnetic pattern ring 12d with two linear Hall sensors, the absolute angle in one cycle of the sine wave pattern can be detected. The control device 1 shown in FIG. 1 is based on the absolute angle (the absolute electrical angle in one pole pair) of the first rotor 11c of the first motor 11 and the second rotor 12c of the second motor 12 detected by the magnetic detector 2. The current flowing through the first coil 11b and the second coil 12b is controlled.

  In order to reduce the influence of leakage magnetic flux from the first motor 11 and the second motor 12, the following method may be used. In the first magnetic pattern ring 11d and the second magnetic pattern ring 12d, a magnetized pattern having a rectangular wave-shaped magnetic flux density distribution is formed separately from the continuous magnetic pattern. The period of the rectangular wave-like magnetized pattern is sufficiently fine. In addition to the linear Hall sensor, the magnetic detector 2 includes a magnetic sensor that detects a magnetic pole direction of a rectangular wave pattern and outputs a pulse.

  First, when the first motor 11 and the second motor 12 are not energized (for example, when the electric vehicle is started), the magnetic detector 2 determines the absolute angles of the first rotor 11c and the second rotor 12c by a continuous magnetic pattern. To detect. Thereafter, the magnetic detector 2 calculates the absolute angle of the first rotor 11c and the second rotor 12c by accumulating the relative rotations of the first rotor 11c and the second rotor 12c detected from the rectangular wave-shaped magnetization pattern. To do. The detection of the relative angle of the first rotor 11c and the second rotor 12c by the rectangular wave-shaped magnetization pattern is more reliable with respect to magnetic noise than the measurement of the absolute angle using a linear Hall sensor. For this reason, if the method mentioned above is used, the reliability at the time of the magnetic detector 2 detecting the absolute angle of the 1st rotor 11c and the 2nd rotor 12c can be improved. Next, control when the electric vehicle drive device 10 is used in an electric vehicle will be described.

  FIG. 8 is a diagram showing the relationship between the rotational force (torque) required for the motor that drives the vehicle and the angular velocity (rotational speed). In general, the relationship between the rotational force (torque) and the angular velocity (rotational speed) of the motor is such that the ratio between the upper limit rotational speed and the maximum rotational speed in a constant rotational force region is about 1: 2. The ratio between the maximum rotational force and the maximum rotational force at the maximum rotational speed is about 2: 1. On the other hand, when the vehicle is driven, the ratio between the upper limit rotation speed and the maximum rotation speed in the constant torque region is about 1: 4 from the vehicle running characteristic curve Ca shown by the solid line in FIG. When the vehicle is driven, the ratio between the maximum rotational force and the maximum rotational force at the maximum rotational speed is about 4: 1.

  Therefore, when the vehicle is driven by a motor, it is preferable to perform a shift in which the ratio (difference between steps) between the first gear ratio and the second gear ratio is about two. By doing in this way, it is possible to cover the running characteristic curve Ca of the vehicle without excess or deficiency in all areas of the NT characteristic (relationship between rotational speed and rotational force) of the motor, and a motor having the minimum necessary output Thus, the power performance necessary for the vehicle can be secured.

  An NT characteristic curve CL indicated by a dotted line in FIG. 8 is the first speed change state (low gear) of the electric vehicle drive device 10, and an NT characteristic curve CH indicated by a one-dot chain line is a second speed change state (high gear) of the electric vehicle drive device 10. ). Thus, by using the first shift state and the second shift state, it is possible to cover the running characteristic curve Ca of the vehicle without excess or deficiency. An NT characteristic curve Cb indicated by a two-dot chain line indicates an NT characteristic that is necessary when an attempt is made to cover the running characteristic curve Ca of the vehicle without shifting. In general, a motor has a ratio of an upper limit rotational speed to a maximum rotational speed in a constant rotational force region, which is about 1: 2, and therefore, when a single motor covers the travel characteristic curve Ca, the motor has an NT characteristic curve. Characteristics such as Cb are required. As a result, excessive performance is required for the motor, resulting in increased waste and increased cost and mass.

  When attention is paid to the motor efficiency, the regions where the motor efficiency is high are the intermediate portions AL, AH of the constant output region (the curve portion of the NT characteristic curve CL or the NT characteristic curve CH) that changes from the maximum rotational force toward the maximum rotational speed. It is in. The electric vehicle drive device 10 can improve efficiency by actively utilizing the intermediate portions AL and AH by shifting. When shifting is not performed, a motor such as the NT characteristic curve Cb is required. In this case, a low-use area in the running characteristic curve Ca (for example, a low speed and high rotational force required area or near the maximum speed). In the area), the motor efficiency becomes the highest. For this reason, from the viewpoint of efficiently using the motor, it is preferable to change the reduction ratio as in the electric vehicle drive device 10.

  When both the first motor 11 and the second motor 12 operate in the electric vehicle drive device 10, the overall reduction ratio R = (α + β−1) / (α−β−1) of the transmission mechanism 13. This is only the first speed change state, and R = 1 in the second speed change state. α is the planetary ratio of the second planetary gear mechanism 30, and β is the planetary ratio of the first planetary gear mechanism 20. The planetary ratio is a value obtained by dividing the number of teeth of the ring gear by the number of teeth of the sun gear. Therefore, the planetary ratio α of the second planetary gear mechanism 30 is the number of teeth of the second ring gear 34 / the number of teeth of the second sun gear 31, and the planetary ratio β of the first planetary gear mechanism 20 is the first ring gear 24. The number of teeth / the number of teeth of the first sun gear 21. In order to realize the interstage difference 2 in the electric vehicle drive device 10 shown in FIG. 1, the planetary ratio α (> 1) of the second planetary gear mechanism 30 is set in the range of 1.90 to 2.10, It is preferable that the planetary ratio β (> 1) of the single planetary gear mechanism 20 is in the range of 2.80 to 3.20.

  Since the electric vehicle drive device 10 is disposed under the spring of the electric vehicle, it is preferably as light as possible. In order to reduce the weight of the electric vehicle drive device 10, there is a method of using aluminum (including an aluminum alloy) for windings (the first coil 11 b and the second coil 12 b) of the first motor 11 and the second motor 12. Since the specific gravity of aluminum is about 30% of the specific gravity of copper, replacing the winding of the first motor 11 and the second motor 12 from copper to aluminum can reduce the mass of the winding by 70%. For this reason, the 1st motor 11, the 2nd motor 12, and the electric vehicle drive device 10 can be reduced in weight. However, since the electrical conductivity of aluminum is generally about 60% of the electrical conductivity of copper used for windings, simply replacing the copper wire with an aluminum wire may lead to a decrease in performance and an increase in heat generation.

  The electric vehicle drive device 10 uses the speed reduction mechanism 40 and changes the speed reduction ratio by the speed change mechanism 13. For this reason, since the rotational force required for the 1st motor 11 and the 2nd motor 12 may be comparatively small, the electric current which flows into the 1st motor 11 and the 2nd motor 12 also becomes comparatively small. For this reason, in this embodiment, even if an aluminum wire is used instead of the copper wire for the first coil 11b of the first motor 11 and the second coil 12b of the second motor 12, the performance deterioration and the heat generation amount increase. It hardly occurs. Therefore, in this embodiment, the electric vehicle drive device 10 is lightened by using aluminum (including an aluminum alloy) for the windings (the first coil 11b and the second coil 12b) of the first motor 11 and the second motor 12. To realize.

  When using aluminum for the windings of the first motor 11 and the second motor 12, it is preferable to use a copper clad aluminum wire. The copper clad aluminum wire is obtained by uniformly coating copper on the outside of an aluminum wire and firmly bonding the boundary between copper and aluminum. The copper clad aluminum wire is easier to solder than the aluminum wire, and the reliability of the connection portion with the terminal is high. Since the specific gravity of copper clad aluminum is about 40% of the specific gravity of copper, replacing the winding of the first motor 11 and the second motor 12 from copper to aluminum can reduce the mass of the winding by 60%. As a result, the first motor 11, the second motor 12, and the electric vehicle drive device 10 can be reduced in weight.

  FIG. 9 is an explanatory diagram showing a configuration of an electric vehicle drive device according to a modification of the present embodiment. The electric vehicle drive device 10a shown in FIG. 9 differs from the electric vehicle drive device 10 of the above-described embodiment in the configuration of the speed change mechanism. In the following, the same components as those of the electric vehicle drive device 10 are denoted by the same reference numerals, and the description thereof is omitted. Electric vehicle drive device 10a includes a speed change mechanism 13a. The speed change mechanism 13a is connected to the first motor 11 to transmit (input) the rotational force output from the first motor 11. The speed change mechanism 13a is connected to the second motor 12 to transmit (input) the rotational force output by the second motor 12. The speed change mechanism 13 a is connected to the speed reduction mechanism 40 by the speed change mechanism input / output shaft 15, and transmits (outputs) the shifted rotational force to the speed reduction mechanism 40. The deceleration mechanism 40 is the same as that of the electric vehicle drive device 10.

  The speed change mechanism 13 a includes a first planetary gear mechanism 70, a second planetary gear mechanism 80, and a clutch device 90. The first planetary gear mechanism 70 is a single pinion type planetary gear mechanism. The first planetary gear mechanism 70 includes a first sun gear 71, a first pinion gear 72, a first carrier 73, and a first ring gear 74. The second planetary gear mechanism 80 is a double pinion planetary gear mechanism. The second planetary gear mechanism 80 includes a second sun gear 81, a second pinion gear 82a, a third pinion gear 82b, a second carrier 83, and a second ring gear 84. The second planetary gear mechanism 80 is disposed closer to the first motor 11 and the second motor 12 than the first planetary gear mechanism 70.

  The second sun gear 81 is supported in the casing G so as to be able to rotate (spin) about the rotation axis R. The second sun gear 81 is connected to the first motor 11. Therefore, when the first motor 11 is operated, the second sun gear 81 is transmitted with the first rotational force TA. Thereby, the second sun gear 81 rotates around the rotation axis R when the first motor 11 is operated. The second pinion gear 82 a meshes with the second sun gear 81. The third pinion gear 82b meshes with the second pinion gear 82a. The second carrier 83 holds the second pinion gear 82a so that the second pinion gear 82a can rotate (rotate) about the second pinion rotation axis Rp2. The second carrier 83 holds the third pinion gear 82b so that the third pinion gear 82b can rotate (spin) about the third pinion rotation axis Rp3. For example, the second pinion rotation axis Rp2 is parallel to the rotation axis R. The third pinion rotation axis Rp3 is parallel to the rotation axis R, for example.

  The second carrier 83 is supported in the casing G so as to be able to rotate around the rotation axis R. As a result, the second carrier 83 has the second pinion gear 82a and the third pinion gear 82a and the third pinion gear 82b so that the second pinion gear 82a and the third pinion gear 82b can revolve around the second sun gear 81, that is, around the rotation axis R. 82b is held. The second ring gear 84 can rotate (spin) about the rotation axis R. The second ring gear 84 meshes with the third pinion gear 82b. The second ring gear 84 is connected to the second motor 12. Therefore, when the second motor 12 is operated, the second ring gear 84 is transmitted with the second rotational force TB. Thus, the second ring gear 84 rotates (spins) about the rotation axis R when the second motor 12 is operated.

  The first sun gear 71 is supported in the casing G so as to be able to rotate (rotate) about the rotation axis R. The first sun gear 71 is connected to the first motor 11 via the second sun gear 81. Specifically, the first sun gear 71 and the second sun gear 81 are formed integrally with the sun gear shaft 64 so as to be rotatable on the same axis (rotation axis R). The sun gear shaft 64 is connected to the first motor 11. As a result, the first sun gear 71 rotates about the rotation axis R when the second motor 12 is operated.

  The first pinion gear 72 meshes with the first sun gear 71. The first carrier 73 holds the first pinion gear 72 so that the first pinion gear 72 can rotate (rotate) about the first pinion rotation axis Rp1. The first pinion rotation axis Rp1 is, for example, parallel to the rotation axis R. The first carrier 73 is supported in the casing G so as to be able to rotate around the rotation axis R. Thus, the first carrier 73 holds the first pinion gear 72 so that the first pinion gear 72 can revolve around the first sun gear 71, that is, around the rotation axis R.

  Further, the first carrier 73 is connected to the second ring gear 84. As a result, the first carrier 73 rotates (spins) about the rotation axis R when the second ring gear 84 rotates (spins). The first ring gear 74 meshes with the first pinion gear 72. The first ring gear 74 is connected to the third sun gear 41 (see FIG. 1) of the speed reduction mechanism 40. With such a structure, when the first ring gear 74 rotates (spins), the third sun gear 41 of the speed reduction mechanism 40 rotates. The clutch device 90 can regulate the rotation of the second carrier 83 in the same manner as the clutch 60 included in the electric vehicle drive device 10 shown in FIG. Specifically, the clutch device 90 can switch between restricting (braking) the rotation of the second carrier 83 around the rotation axis R and allowing the rotation. The electric vehicle driving device 10a has the same effect as the electric vehicle driving device 10 based on the same principle as the electric vehicle driving device 10 described above.

DESCRIPTION OF SYMBOLS 1 Control apparatus 2 Magnetic detector 10, 10a Electric vehicle drive device 11 1st motor 12 2nd motor 13, 13a Transmission mechanism 14, 94 Sun gear shaft 15 Transmission mechanism input / output shaft 16 Reduction mechanism input / output shaft 20, 70 First planet Gear mechanism 21, 71 First sun gear 22, 72 First pinion gear 23, 73 First carrier 24, 74 First ring gear 30, 80 Second planetary gear mechanism 31, 81 Second sun gear 32a, 82a Second pinion gear 32b 82b Third pinion gears 33, 83 Second carriers 34, 84 Second ring gear 40 Reduction mechanism 41 Third sun gear 41S Third sun gear shaft 42 Fourth pinion gear 43 Third carrier 44 Third ring gear 45 Outer rings 60, 90 Clutch device 61 Inner ring 62 Outer ring G Casing H Wheel

Claims (5)

A first motor;
A second motor;
A first sun gear coupled to the first motor;
A first pinion gear meshing with the first sun gear;
A first carrier that holds the first pinion gear so that the first pinion gear can rotate and the first pinion gear can revolve around the first sun gear;
A clutch device capable of regulating rotation of the first carrier;
A first ring gear meshing with the first pinion gear and coupled to the second motor;
A second sun gear coupled to the first motor;
A second pinion gear meshing with the second sun gear;
A third pinion gear meshing with the second pinion gear;
The second pinion gear and the third pinion gear can rotate around the second pinion gear and the third pinion gear so that the second pinion gear and the third pinion gear can revolve around the second sun gear, respectively. A second carrier for holding the third pinion gear and coupled to the first ring gear;
A second ring gear meshing with the third pinion gear;
A third sun gear coupled to the second ring gear;
A fourth pinion gear meshing with the third sun gear;
The fourth pinion gear is held so that the fourth pinion gear can rotate and the fourth pinion gear can revolve around the third sun gear, and the third pinion gear is connected to the wheel of the electric vehicle. Career,
A third ring gear meshing with the fourth pinion gear and fixed to the stationary system;
An in-wheel motor comprising: A first motor;
A second motor;
A first sun gear coupled to the first motor;
A first pinion gear meshing with the first sun gear;
A first carrier that holds the first pinion gear so that the first pinion gear can rotate and the first pinion gear can revolve around the first sun gear;
A first ring gear meshing with the first pinion gear;
A second sun gear coupled to the first motor;
A second pinion gear meshing with the second sun gear;
A third pinion gear meshing with the second pinion gear;
The second pinion gear and the third pinion gear can rotate around the second pinion gear and the third pinion gear so that the second pinion gear and the third pinion gear can revolve around the second sun gear, respectively. A second carrier holding a third pinion gear;
A clutch device capable of regulating rotation of the second carrier;
A second ring gear meshing with the third pinion gear, coupled to the first carrier, and coupled to the second motor;
A third sun gear coupled to the first ring gear;
A fourth pinion gear meshing with the third sun gear;
The fourth pinion gear is held so that the fourth pinion gear can rotate and the fourth pinion gear can revolve around the third sun gear, and the third pinion gear is connected to the wheel of the electric vehicle. Career,
A third ring gear meshing with the fourth pinion gear and fixed to the stationary system;
An in-wheel motor comprising: The clutch device is
A first member;
A second member rotatable relative to the first member;
When a rotational force in the first direction acts on the second member, the rotational force is transmitted between the first member and the second member, and the second member has a second direction opposite to the first direction. An engaging member that does not transmit a rotational force between the first member and the second member when a rotational force acts;
The in-wheel motor according to claim 1, wherein the in-wheel motor is a one-way clutch device. The one-way clutch device is
The said 1st motor is arrange | positioned in the direction which rotates in the direction which advances the electric vehicle by which the said in-wheel motor is mounted, and engages when the said 2nd motor is not driven. In-wheel motor.   The in-wheel motor according to claim 4, wherein the clutch device is a sprag type one-way clutch.

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