Vehicle drive unit

Abstract

In the present invention, a backlash in the rotational direction is present between a lock member in a lock position and a first rotating member. By setting, as a detected rotational position, the rotational position of a target rotating member which is detected by a rotational position sensor in the lock state of a parking lock mechanism and setting, as a theoretical lock position, the rotational position of the target rotating member in which the backlash is assumed not to be present in the lock state of the parking lock mechanism, a control device performs torque direction determination processing for determining a wheel torque direction (Ct) on the basis of the displacement direction of the detected rotational position with respect to the theoretical lock position due to the backlash.

Description

[Technical Field]

[0001] The present invention relates to a vehicle drive device including a rotating electric machine that functions as a drive force source for wheels, and a parking lock mechanism that selectively restricts rotation of a rotating member that rotates in conjunction with the wheels. [Background technology]

[0002] An example of such a vehicle drive device is disclosed in the following Patent Document 1. In the following description of the background art, the reference numerals in Patent Document 1 will be cited in parentheses.

[0003] In the vehicle drive device (10) disclosed in Patent Document 1, the parking lock mechanism (78) includes a parking lock gear (76) arranged in a power transmission path connecting the rotating electric machine (12) and the wheels (68, 74), a parking pole (80) that restricts the rotation of the parking lock gear, and a drive device (82) that drives the parking pole (see Figure 1 of Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-264908 Summary of the Invention [Problem to be solved by the invention]

[0005] When a vehicle is parked on an inclined road, torque is transmitted from the wheels (68, 74) to the parking lock gear (76) due to the vehicle's own weight, and a load acts on the engagement portion between the parking lock gear (76) and the parking pole (80). As a result, the driving force of the drive unit (82) may not be enough to disengage the parking pole (80) from the parking lock gear (76).

[0006] Patent Document 1 discloses that in the above case, the torque of the rotating electric machine (12) is controlled so as to reduce the load acting on the engagement portion between the parking lock gear (76) and the parking pole (80).

[0007] However, Patent Document 1 does not disclose how to determine the direction of the load acting on the engagement portion between the parking lock gear (76) and the parking pole (80). Therefore, in the vehicle drive device (10), it is difficult to appropriately control the torque of the rotating electric machine (12) so as to reduce the load acting on the engagement portion between the parking lock gear (76) and the parking pole (80).

[0008] Therefore, it is desirable to realize a vehicle drive device that can appropriately control the torque of the rotating electric machine when unlocking the parking lock mechanism. [Means for solving the problem]

[0009] In view of the above, the characteristic configuration of the vehicle drive device is as follows: a rotating electric machine that functions as a driving force source for the wheels; a parking lock mechanism that selectively restricts rotation of a first rotating member that rotates in conjunction with the wheel; a second rotating member that rotates in conjunction with the wheel and is disposed closer to the wheel than the first rotating member in a power transmission path that connects the rotating electric machine and the wheel; and a rotational position sensor that detects the rotational position of either the first rotating member or the second rotating member as a target rotating member; a control device that acquires a detection value of the rotational position sensor and controls the rotating electric machine and the parking lock mechanism, the parking lock mechanism includes a locking member that is movable between a locked position where the locking member engages with the first rotating member to restrict rotation of the first rotating member and an unlocked position where the locking member is separated from the first rotating member to allow rotation of the first rotating member; and a drive device that drives the locking member, a backlash in a rotational direction exists between the locking member in the locked position and the first rotating member, The state of the parking lock mechanism when the locking member is in the locked position is defined as a locked state, the rotational position of the target rotating member detected by the rotational position sensor in the locked state is defined as a detected rotational position, and the rotational position of the target rotating member in the locked state when no backlash exists is defined as a theoretical locked position, The control device executes a torque direction determination process to determine the wheel torque direction, which is the direction of the torque being transmitted from the wheel to the first rotating member, based on the direction of deviation of the detected rotational position from the theoretical lock position due to the backlash.

[0010] According to this characteristic configuration, the torque direction determination process determines the wheel torque direction based on the direction of deviation of the detected rotational position from the theoretical lock position due to backlash. This allows the rotating electric machine to appropriately output torque in a direction that weakens the engagement force between the locking member and the first rotating member. Therefore, when unlocking the parking lock mechanism, the torque of the rotating electric machine can be appropriately controlled. In this way, even when the locking member cannot be moved from the locked position to the unlocked position by the driving force of the drive device, the torque of the rotating electric machine can be used to weaken the engagement force between the locking member and the first rotating member, allowing the parking lock mechanism to be unlocked by the driving force of the drive device. Furthermore, this characteristic configuration eliminates the need for various sensors such as tilt angle sensors for determining the wheel torque direction, which makes it easier to simplify the configuration of the vehicle drive system and reduce costs. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view showing a part of a vehicle drive device according to an embodiment; [Figure 2] 1 is a skeleton diagram of a vehicle drive device according to an embodiment; [Figure 3]FIG. 10 is a diagram showing the positional relationship between the target rotating member and the locking member in the theoretical lock position. [Figure 4] Control block diagram of a vehicle drive device according to an embodiment [Figure 5] FIG. 10 is a diagram showing the positional relationship between the target rotating member and the locking member when torque is transmitted to the target rotating member in one circumferential direction. [Figure 6] FIG. 10 is a diagram showing the positional relationship between the target rotating member and the locking member when torque is transmitted to the target rotating member in one circumferential direction. [Figure 7] FIG. 10 is a diagram showing the positional relationship between the target rotating member and the locking member when torque is transmitted to the target rotating member in one circumferential direction. [Figure 8] FIG. 10 is a diagram illustrating the positional relationship between the target rotating member and the locking member when torque is transmitted to the target rotating member toward the other circumferential side; [Figure 9] FIG. 10 is a diagram illustrating the positional relationship between the target rotating member and the locking member when torque is transmitted to the target rotating member toward the other circumferential side; [Figure 10] FIG. 10 is a diagram illustrating the positional relationship between the target rotating member and the locking member when torque is transmitted to the target rotating member toward the other circumferential side; [Figure 11] 10 is a flowchart showing an example of a torque direction determination process and an unlocking assistance process performed by a control device. DETAILED DESCRIPTION OF THE INVENTION

[0012] A vehicle drive device 100 according to an embodiment will be described below with reference to the drawings. As shown in Fig. 1, the vehicle drive device 100 includes a rotating electric machine 1, a rotational position sensor 8, and a parking lock mechanism 10.

[0013] The rotating electric machine 1 functions as a driving force source for wheels W (see FIG. 2) equipped on a vehicle. The rotating electric machine 1 has a function as a motor (electric motor) that receives a supply of electric power to generate power, and a function as a generator that receives a supply of power to generate electric power. Specifically, the rotating electric machine 1 is electrically connected to an electric storage device (not shown) such as a battery or a capacitor. The rotating electric machine 1 generates driving force by running using the electric power stored in the electric storage device. The rotating electric machine 1 also generates power using the driving force transmitted from the wheels W to charge the electric storage device.

[0014] The rotating electric machine 1 includes a stator 11 and a rotor 12. The stator 11 includes a cylindrical stator core 11a. The stator core 11a is fixed to a non-rotating member NR. The rotor 12 includes a cylindrical rotor core 12a. The rotor core 12a is rotatably supported relative to the stator core 11a. In this embodiment, the rotor 12 further includes a rotor shaft 12b connected to the rotor core 12a so as to rotate integrally with the rotor core 12a.

[0015] In the following description, the direction along the rotational axis of the rotor 12 is referred to as the "axial direction L." One side of the axial direction L is referred to as the "first axial side L1," and the other side of the axial direction L is referred to as the "second axial side L2." The direction perpendicular to the axial direction L is referred to as the "radial direction R." The radial direction R is defined based on the rotational axis of each rotating member, such as the rotor 12. Note that when it is not necessary to distinguish which rotational axis is used as the reference or when it is clear which rotational axis is used as the reference, the direction may simply be referred to as the "radial direction R."

[0016] In this embodiment, the rotor shaft 12b is formed in a cylindrical shape having an axis along the axial direction L. The rotor shaft 12b is disposed so as to protrude from the rotor core 12a to both a first axial side L1 and a second axial side L2.

[0017] In this embodiment, the rotating electric machine 1 is an inner rotor type rotating electric machine. Therefore, the rotor core 12a is arranged inside the stator core 11a in the radial direction R. Furthermore, the rotor shaft 12b is arranged inside the rotor core 12a in the radial direction R.

[0018] In this embodiment, the rotating electric machine 1 is a rotating field type rotating electric machine. Therefore, a stator coil is wound around the stator core 11a. In this embodiment, the stator coil is wound around the stator core 11a so that coil end portions 11b are formed that protrude from the stator core 11a toward both the first axial side L1 and the second axial side L2. Although not shown, a permanent magnet is provided in the rotor core 12a.

[0019] The rotational position sensor 8 is a sensor for detecting the rotational position of a target rotating member T, which is either the first rotating member RT1 or the second rotating member RT2. In this embodiment, the target rotating member T is the first rotating member RT1. The first rotating member RT1 is the rotor shaft 12b.

[0020] Each of the first rotating member RT1 and the second rotating member RT2 is a rotating member that rotates in conjunction with a wheel W (see FIG. 2). The second rotating member RT2 is disposed closer to the wheel W than the first rotating member RT1 in the power transmission path that connects the rotating electric machine 1 and the wheel W.

[0021] The parking lock mechanism 10 selectively restricts the rotation of the first rotating member RT1. The detailed configuration of the parking lock mechanism 10 will be described later.

[0022] As shown in FIG. 2, in this embodiment, the vehicle drive device 100 further includes a power transmission mechanism 2, a differential gear mechanism 3, and a case 9.

[0023] The power transmission mechanism 2 transmits the rotation of the rotor 12 to the differential gear mechanism 3. In this embodiment, the power transmission mechanism 2 includes a planetary gear mechanism 21, a first gear 22, and a second gear 23. In this embodiment, the planetary gear mechanism 21 and the first gear 22 are arranged on a first axis X1, which is the rotation axis of the rotor 12. The second gear 23 is arranged on a second axis X2, which is different from the first axis X1.

[0024] The planetary gear mechanism 21 is configured to reduce the rotation speed of the rotor 12 and transmit the rotation to the first gear 22. The planetary gear mechanism 21 includes a sun gear SG, a carrier CR, and a ring gear RG.

[0025] The sun gear SG is connected to the rotor 12 so as to rotate integrally with it. In other words, the sun gear SG is an input element of the planetary gear mechanism 21. In this embodiment, the sun gear SG is connected to the rotor shaft 12b via an input shaft I so as to rotate integrally with it. The input shaft I is formed to extend along the axial direction L. In this embodiment, the input shaft I is formed to extend from the sun gear SG to a first axial side L1.

[0026] The carrier CR rotatably supports a first pinion gear PG1 and a second pinion gear PG2, which rotate integrally with each other. Each of the first pinion gear PG1 and the second pinion gear PG2 rotates (spins) around its own axis and also rotates (revolves) together with the carrier CR around the sun gear SG. A plurality of the first pinion gears PG1 and the second pinion gears PG2 are provided at intervals from each other along their own orbital loci.

[0027] The first pinion gear PG1 meshes with the sun gear SG. The second pinion gear PG2 meshes with the ring gear RG. The second pinion gear PG2 has a smaller diameter than the first pinion gear PG1. In this embodiment, the second pinion gear PG2 is disposed on the first axial side L1 of the first pinion gear PG1.

[0028] The carrier CR is connected to the first gear 22 so as to rotate integrally with the first gear 22. In other words, the carrier CR is an output element of the planetary gear mechanism 21. In this embodiment, the first gear 22 is disposed on the second axial side L2 with respect to the planetary gear mechanism 21. In this embodiment, the first gear 22 is the second rotating member RT2.

[0029] The ring gear RG is fixed to the non-rotating member NR. In this embodiment, the ring gear RG is fixed to a case 9 serving as the non-rotating member NR.

[0030] The first gear 22 and the second gear 23 mesh with each other. In this embodiment, the second gear 23 is formed to have a larger diameter than the first gear 22. Therefore, in this embodiment, the rotation of the carrier CR of the planetary gear mechanism 21 is reduced between the first gear 22 and the second gear 23 and then transmitted to the differential gear mechanism 3.

[0031] The differential gear mechanism 3 distributes the rotation transmitted from the power transmission mechanism 2 to a pair of wheels W. In this embodiment, the differential gear mechanism 3 is disposed on the second axis X2.

[0032] In this embodiment, the differential gear mechanism 3 is a bevel gear type differential gear mechanism. Specifically, the differential gear mechanism 3 includes a pair of pinion gears, a first side gear and a second side gear that mesh with the pair of pinion gears, and a differential case that houses these gears.

[0033] In this embodiment, the differential case is connected to the second gear 23 so as to rotate integrally therewith. The differential case is also connected to a pinion shaft that rotatably supports a pair of pinion gears so as to rotate integrally therewith. In this embodiment, the first side gear is connected to a first drive shaft DS1, which is drivingly connected to a wheel W on a first axial side L1, via a transmission shaft 35 extending along the axial direction L, so as to rotate integrally therewith. The second side gear is connected to a second drive shaft DS2, which is drivingly connected to a wheel W on a second axial side L2, so as to rotate integrally therewith.

[0034] The case 9 accommodates the rotating electric machine 1, the power transmission mechanism 2, the differential gear mechanism 3, and the parking lock mechanism 10. As shown in Fig. 1 , in this embodiment, the case 9 includes a first cylindrical portion 91, a second cylindrical portion 92, a third cylindrical portion 93, a first side wall portion 94, a second side wall portion 95, and a third side wall portion 96.

[0035] Each of the first cylindrical portion 91 and the second cylindrical portion 92 is formed in a cylindrical shape concentric with the rotor 12. In the present embodiment, the first cylindrical portion 91 is disposed radially outward from a portion of the rotor shaft 12b that protrudes from the rotor core 12a toward the first axial side L1. The second cylindrical portion 92 is disposed radially inward from a portion of the rotor shaft 12b that protrudes from the rotor core 12a toward the first axial side L1. In the present embodiment, the rotor shaft 12b is rotatably supported with respect to the case 9 via a first rotor bearing B1 that is disposed between the rotor shaft 12b and the first cylindrical portion 91 in the radial direction R.

[0036] The first side wall portion 94 is formed to extend outward in the radial direction R from the first cylindrical portion 91. The first side wall portion 94 is arranged to cover a first axial side L1 of the rotating electrical machine 1. The second side wall portion 95 is formed to extend inward in the radial direction R from the first cylindrical portion 91. The second side wall portion 95 is arranged closer to the first axial side L1 than the first side wall portion 94. In this embodiment, the second side wall portion 95 is connected to an end of the first cylindrical portion 91 on the first axial side L1 so as to cover the first cylindrical portion 91 from the first axial side L1. In addition, in this embodiment, the second cylindrical portion 92 is formed to extend from the second side wall portion 95 to a second axial side L2.

[0037] The third cylindrical portion 93 is formed in a cylindrical shape concentric with the rotor 12. In this embodiment, a portion of the rotor shaft 12b that protrudes from the rotor core 12a toward the second axial side L2 has a small-diameter portion 12c that is formed with a smaller diameter than a portion of the rotor shaft 12b that is connected to the rotor core 12a. The third cylindrical portion 93 is disposed further outward in the radial direction R than the small-diameter portion 12c of the rotor shaft 12b. In this embodiment, the rotor shaft 12b is rotatably supported with respect to the case 9 via a second rotor bearing B2 that is disposed between the small-diameter portion 12c and the third cylindrical portion 93 in the radial direction R.

[0038] The third side wall portion 96 is formed to extend outward in the radial direction R from the third cylindrical portion 93. The third side wall portion 96 is arranged to cover the second axial side L2 of the rotating electric machine 1. In the present embodiment, the third cylindrical portion 93 is formed to extend from an inner end portion of the third side wall portion 96 in the radial direction R to the second axial side L2.

[0039] 1, the rotational position sensor 8 includes a sensor stator 81 fixed to a non-rotating member NR, and a sensor rotor 82 rotatably supported relative to the sensor stator 81. In this embodiment, the rotational position sensor 8 is configured as a resolver. Therefore, when an AC current is passed through a coil provided in the sensor stator 81, the rotational position sensor 8 detects the phase of an AC voltage corresponding to the relative angle of the sensor rotor 82 with respect to the sensor stator 81, thereby detecting the rotational position of the target rotating member T. Note that the rotational position sensor 8 is not limited to a resolver and can be configured using various sensors, such as a Hall element sensor, an encoder, or a magnetic rotation sensor.

[0040] In this embodiment, the sensor stator 81 is fixed to a third side wall portion 96 of the case 9 serving as a non-rotating member NR. The sensor stator 81 is disposed so as to protrude inward in the radial direction R from a third cylindrical portion 93 of the case 9. The sensor rotor 82 is coupled to the small diameter portion 12c so as to rotate integrally with the rotor shaft 12b serving as the target rotating member T. The sensor rotor 82 is disposed so as to face the sensor stator 81 from the inside in the radial direction R.

[0041] The parking lock mechanism 10 includes a lock member 4 and a drive device 5.

[0042] The locking member 4 is configured to be movable between a locked position P1 where it engages with the first rotating member RT1 to restrict rotation of the first rotating member RT1, and an unlocked position P2 where it is separated from the first rotating member RT1 to allow rotation of the first rotating member RT1. The locking member 4 is supported so as not to rotate relative to the non-rotating member NR. In this embodiment, the locking member 4 includes a cylindrical portion 41 formed in a cylindrical shape concentric with the rotor 12. The cylindrical portion 41 is disposed radially outward of the second cylindrical portion 92 of the case 9.

[0043] The locking member 4 has a plurality of first engaging portions 411. The case 9 has a plurality of first engaged portions 921 with which the plurality of first engaging portions 411 engage. In the following description, the direction along the rotation direction of the first rotating member RT1 is referred to as the "circumferential direction C." One side of the circumferential direction C is referred to as the "first circumferential side C1," and the other side of the circumferential direction C is referred to as the "second circumferential side C2."

[0044] As shown in FIG. 3, the multiple first engaging portions 411 and the multiple first engaged portions 921 are arranged in the circumferential direction C. In this embodiment, each of the multiple first engaging portions 411 is a tooth portion formed on the inner circumferential surface of the cylindrical portion 41 of the locking member 4. Furthermore, each of the multiple first engaged portions 921 is a tooth portion formed on the outer circumferential surface of the second cylindrical portion 92 of the case 9. The multiple first engaging portions 411 are meshed with the multiple first engaged portions 921 so as to be movable in the axial direction L but not rotatable relative to each other. In the example shown in FIGS. 1 and 3, the multiple first engaging portions 411 and the multiple first engaged portions 921 are arranged at equal intervals in the circumferential direction C and are formed continuously along the axial direction L.

[0045] The locking member 4 also has second engaging portions 412. The first rotating member RT1 has a plurality of second engaged portions Ta with which the second engaging portions 412 engage. In this embodiment, the second engaging portions 412 correspond to the "engaging portions," and the second engaged portions Ta correspond to the "engaged portions."

[0046] The second engaged portions Ta are arranged in the circumferential direction C. In this embodiment, each of the second engaged portions Ta is a tooth portion formed on the inner circumferential surface of the first rotating member RT1 (here, the rotor shaft 12b). In the example shown in FIG. 3, the second engaged portions Ta are arranged at equal intervals in the circumferential direction C.

[0047] In this embodiment, the plurality of second engagement portions 412 are arranged in the circumferential direction C. Each of the plurality of second engagement portions 412 is a tooth portion formed on the outer circumferential surface of the cylindrical portion 41 of the locking member 4. In the example shown in FIG. 3, the plurality of second engagement portions 412 are arranged at equal intervals in the circumferential direction C.

[0048] In this embodiment, the plurality of second engaging portions 412 are configured to engage with the plurality of second engaged portions Ta from the first axial side L1 and restrict rotation of the first rotating member RT1. In the example shown in Fig. 1, the plurality of second engaging portions 412 are formed continuously from the end face of the cylindrical portion 41 on the second axial side L2 toward the first axial side L1. Furthermore, the plurality of second engaged portions Ta are formed continuously from the end face of the rotor shaft 12b on the first axial side L1 toward the second axial side L2.

[0049] In the following description, the state of the parking lock mechanism 10 when the locking member 4 is in the locked position P1 will be referred to as the "locked state," and the state of the parking lock mechanism 10 when the locking member 4 is in the unlocked position P2 will be referred to as the "unlocked state."

[0050] In this embodiment, when the locking member 4 moves from the unlocked position P2 to the second axial side L2 and is at the locked position P1, the multiple second engaging portions 412 of the tubular portion 41 engage with the multiple second engaged portions Ta of the first rotating member RT1, and the parking lock mechanism 10 is in a locked state. On the other hand, when the locking member 4 is at the unlocked position P2, the locking member 4 moves away from the first rotating member RT1 to the first axial side L1, and the parking lock mechanism 10 is in an unlocked state. Note that in this embodiment, not only the position furthest to the first axial side L1 in the movable range of the locking member 4, but also the position furthest to the second axial side L2 from that position corresponds to the unlocked position P2. In other words, in this embodiment, when the locking member 4 is within a predetermined range from the position closest to the first axial side L1 to the second axial side L2 in the movable range, the multiple second engaging portions 412 do not engage with the multiple second engaged portions Ta, and when the locking member 4 moves from that range to the second axial side L2, the multiple second engaging portions 412 engage with the multiple second engaged portions Ta.

[0051] 1, the driving device 5 is a device that drives the locking member 4. In this embodiment, the driving device 5 includes a position maintaining unit 6 and an electromagnetic driving unit 7.

[0052] The position maintaining unit 6 includes a permanent magnet 61 supported by the locking member 4. The position maintaining unit 6 maintains the locking member 4 at either the locked position P1 or the unlocked position P2 by the magnetic force of the permanent magnet 61. The permanent magnet 61 may be formed by joining a plurality of split magnets together.

[0053] The permanent magnet 61 has an N pole and an S pole. In this embodiment, the permanent magnet 61 is arranged so that the N pole and the S pole are aligned in the axial direction L. Specifically, the permanent magnet 61 is arranged so that the N pole and the S pole are aligned in the axial direction L on the side of the electromagnetic drive unit 7 (outside in the radial direction R in this embodiment). For example, one permanent magnet 61 is arranged so that the N pole and the S pole of the permanent magnet 61 are aligned in the axial direction L on the side of the electromagnetic drive unit 7, or two permanent magnets 61 are arranged so that the N pole of one permanent magnet 61 and the S pole of the other permanent magnet 61 are aligned in the axial direction L on the side of the electromagnetic drive unit 7. In the following description, one of the N pole and the S pole of the permanent magnet 61 is referred to as a "first pole 61A" and the other is referred to as a "second pole 61B." The permanent magnets 61 are arranged so that the first pole 61A and the second pole 61B are aligned in this order from the first axial side L1 to the second axial side L2.

[0054] In this embodiment, the permanent magnet 61 is formed in a cylindrical shape concentric with the rotor 12. The permanent magnet 61 is fixed to the cylindrical portion 41 of the locking member 4. In the example shown in FIG. 1 , the permanent magnet 61 is fixed to a portion of the outer circumferential surface of the cylindrical portion 41 that is closer to the first axial side L1 than the second engagement portion 412.

[0055] The electromagnetic drive unit 7 uses electromagnetic force generated by power from a power source (not shown) to move the locking member 4 from the unlocked position P2 to the locked position P1, and from the locked position P1 to the unlocked position P2. In this embodiment, the electromagnetic drive unit 7 is formed in a cylindrical shape concentric with the permanent magnet 61. In this embodiment, the electromagnetic drive unit 7 includes a fixed portion 70, a first magnetic body portion 71, a second magnetic body portion 72, a third magnetic body portion 73, and a coil 74.

[0056] The fixed portion 70 is fixed to the non-rotating member NR. In this embodiment, the fixed portion 70 is formed in a cylindrical shape that is concentric with the first cylindrical portion 91 of the case 9. The fixed portion 70 is fixed to the inner circumferential surface of the first cylindrical portion 91.

[0057] The first magnetic body portion 71, the second magnetic body portion 72, and the third magnetic body portion 73 are each made of a magnetic material. The first magnetic body portion 71, the second magnetic body portion 72, and the third magnetic body portion 73 are arranged in the order described above with a gap between them in the axial direction L. In this embodiment, the first magnetic body portion 71, the second magnetic body portion 72, and the third magnetic body portion 73 are formed to protrude inward in the radial direction R from the fixed portion 70. The first magnetic body portion 71, the second magnetic body portion 72, and the third magnetic body portion 73 are arranged in the order described above from the first axial side L1 to the second axial side L2.

[0058] The coil 74 is configured to generate, when energized, a magnetic flux that passes through the first magnetic body portion 71, the second magnetic body portion 72, and the third magnetic body portion 73. In this embodiment, the coil 74 is wound around the inner circumferential surface of the fixed portion 70 between the first magnetic body portion 71 and the second magnetic body portion 72 in the axial direction L, and between the second magnetic body portion 72 and the third magnetic body portion 73 in the axial direction L.

[0059] As shown in FIG. 4, the vehicle drive system 100 includes a control device 20 that controls the rotating electric machine 1 and the parking lock mechanism 10.

[0060] In this embodiment, the control device 20 controls the operation of the locking member 4 by controlling the current flowing through the coil 74. Explaining further, when the control device 20 does not flow current through the coil 74 and the locking member 4 is in the unlocked position P2, the first pole 61A attracts the first magnetic material portion 71, and the second pole 61B attracts the second magnetic material portion 72. When the control device 20 moves the locking member 4 from the unlocked position P2 to the locked position P1, the control device 20 flows current through the coil 74 so that the first magnetic material portion 71 becomes a pole that repels the first pole 61A, the second magnetic material portion 72 becomes a pole that repels the second pole 61B, and the third magnetic material portion 73 becomes a pole that attracts the second pole 61B. Furthermore, when the control device 20 does not pass a current through the coil 74 and the locking member 4 is in the locked position P1, the first pole 61A attracts the second magnetic material portion 72, and the second pole 61B attracts the third magnetic material portion 73. When the control device 20 moves the locking member 4 from the locked position P1 to the unlocked position P2, the control device 20 passes a current through the coil 74 so that the second magnetic material portion 72 becomes a pole that repels the first pole 61A, the third magnetic material portion 73 becomes a pole that repels the second pole 61B, and the first magnetic material portion 71 becomes a pole that attracts the first pole 61A.

[0061] Incidentally, when a vehicle equipped with the vehicle driving device 100 is parked on an inclined road surface, torque is transmitted from the wheels W to the first rotating member RT1 (here, the rotor shaft 12b) due to the vehicle's own weight. Therefore, torque acts on the first rotating member RT1 so as to strengthen the engagement force between the locking member 4 and the first rotating member RT1 (here, the engagement force between the second engaging portion 412 and the second engaged portion Ta).

[0062] At this time, depending on the strength of the engagement force between the locking member 4 and the first rotating member RT1, the driving force (electromagnetic force in this case) of the drive unit 5 may not be enough to disengage the locking member 4 from the first rotating member RT1. Therefore, when the drive unit 5 generates a driving force for moving the locking member 4 from the locked position P1 to the unlocked position P2, the control device 20 executes an unlock assistance process to cause the rotating electric machine 1 to output torque in the opposite direction to the wheel torque direction Ct, which is the direction of the torque being transmitted from the wheel W to the first rotating member RT1. The unlock assistance process can weaken the engagement force between the locking member 4 and the first rotating member RT1, so that the drive force of the drive unit 5 can be used to disengage the locking member 4 from the first rotating member RT1.

[0063] Furthermore, when executing the unlock assist process, the control device 20 executes a torque direction determination process to determine the wheel torque direction Ct. Here, backlash exists in the rotational direction (circumferential direction C) between the locking member 4 in the locked position P1 and the first rotating member RT1. Therefore, when a vehicle equipped with the vehicle driving device 100 is parked on an inclined road surface, a deviation in the rotational position of the target rotating member T occurs due to the backlash. Therefore, in the torque direction determination process, the control device 20 determines the wheel torque direction Ct based on the direction of deviation of the detected rotational position from the theoretical lock position P0 due to the backlash. Here, the "theoretical lock position P0" is the rotational position of the target rotating member T in the locked state of the parking lock mechanism 10 when no backlash exists (the rotational position of the target rotating member T shown in FIG. 3). Furthermore, the "detected rotational position" is the rotational position of the target rotating member T detected by the rotational position sensor 8 in the locked state of the parking lock mechanism 10.

[0064] In this embodiment, the control device 20 determines the wheel torque direction Ct based on the remainder when θ is divided by (360 / N). Here, "θ" is the detected rotational position [°]. "N" is the number [number] of second engaged portions Ta, and " / " is the division operator. Therefore, "360 / N" represents the pitch [°] between adjacent second engaged portions Ta.

[0065] An example of the torque direction determination process by the control device 20 will be described below with reference to Figures 5 to 10. In the example shown in Figures 5 to 10, the number of second engaged portions Ta is 12 (N = 12). Therefore, in this example, the pitch between adjacent second engaged portions Ta is 30° (360 / N = 360 / 12 = 30).

[0066] 5 to 7 are diagrams showing the positional relationship between the rotor shaft 12b and the locking member 4 when torque is transmitted toward the first circumferential side C1 to the rotor shaft 12b as the first rotating member RT1 and the target rotating member T. Also, FIGS. 8 to 10 are diagrams showing the positional relationship between the rotor shaft 12b and the locking member 4 when torque is transmitted toward the second circumferential side C2 to the first rotating member RT1 and the rotor shaft 12b as the target rotating member T.

[0067] In this embodiment, the rotational position sensor 8 is set so that the detected value of the rotational position of the target rotating member T is zero at one of N theoretical lock positions P0. Here, the rotational position sensor 8 is set so that the detected value of the rotational position of the target rotating member T at the theoretical lock position P0 shown in FIG. 3 is zero (θ=0).

[0068] According to this configuration, the calculation process for determining the wheel torque direction Ct can be simplified.

[0069] The rotor shaft 12b shown in Fig. 5 is rotated by an amount corresponding to the backlash toward the first circumferential side C1 from the rotational position (theoretical lock position P0) of the rotor shaft 12b shown in Fig. 3. In the example shown in Fig. 5, the detected rotational position is 5° (θ=5).

[0070] The rotor shaft 12b shown in Fig. 6 is in a state where its rotational position is shifted by 30° toward the first circumferential side C1 from the rotor shaft 12b shown in Fig. 5. In other words, the multiple second engaged portions Ta shown in Fig. 6 are engaged with the multiple second engaging portions 412 at positions shifted by one second engaged portion Ta toward the first circumferential side C1 from the multiple second engaged portions Ta shown in Fig. 5. Therefore, in the example shown in Fig. 6, the detected rotational position is 35° (θ=35).

[0071] The rotor shaft 12b shown in Fig. 7 is in a state where its rotational position is shifted by 30° toward the first circumferential side C1 from the rotor shaft 12b shown in Fig. 6. In other words, the multiple second engaged portions Ta shown in Fig. 7 are engaged with the multiple second engaging portions 412 at positions shifted by one second engaged portion Ta toward the first circumferential side C1 from the multiple second engaged portions Ta shown in Fig. 6. Therefore, in the example shown in Fig. 7, the detected rotational position is 65° (θ=65).

[0072] 8 is rotated by an amount corresponding to backlash toward the second circumferential side C2 from the rotational position (theoretical lock position P0) of rotor shaft 12b shown in FIG. 3. In the example shown in FIG. 8, the detected rotational position is 85° (θ=85). In this example, rotational position sensor 8 is a resolver with four poles, and therefore the detected rotational position is detected in the range of 0 to 90°. Therefore, 85° in this example corresponds to −5° (see θ′ shown in FIG. 8) when it is assumed that the rotational position sensor 8 detects the detected rotational position in the range of −180 to 180°.

[0073] The rotor shaft 12b shown in Fig. 9 is shifted in rotational position by 30° toward the second circumferential side C2 from the rotor shaft 12b shown in Fig. 8. That is, the second engaged portions Ta shown in Fig. 9 are engaged with the second engaging portions 412 at positions shifted by one second engaged portion Ta toward the second circumferential side C2 from the second engaged portions Ta shown in Fig. 8. Therefore, in the example shown in Fig. 9, the detected rotational position is 55° (θ=55). Note that 55° in this example corresponds to -35° (see θ' shown in Fig. 9) when a rotational position sensor 8 that detects the detected rotational position in the range of -180 to 180° is used.

[0074] The rotor shaft 12b shown in Fig. 10 is shifted in rotational position by 30° toward the second circumferential side C2 from the rotor shaft 12b shown in Fig. 9. That is, the second engaged portions Ta shown in Fig. 10 are engaged with the second engaging portions 412 at positions shifted by one second engaged portion Ta toward the second circumferential side C2 from the second engaged portions Ta shown in Fig. 9. Therefore, in the example shown in Fig. 10, the detected rotational position is 25° (θ=25). Note that 25° in this example corresponds to -65° (see θ' shown in Fig. 10) when a rotational position sensor 8 that detects the detected rotational position in the range of -180 to 180° is used.

[0075] In the examples shown in Figures 5 to 7, the remainder when θ is divided by (360 / N) is 5°. In the examples shown in Figures 8 to 10, the remainder when θ is divided by (360 / N) is 25°. Note that "r" shown in Figures 5 to 10 is the remainder when θ is divided by (360 / N).

[0076] In this way, the remainder when θ is divided by (360 / N) is divided into two groups depending on whether the wheel torque direction Ct is toward the first circumferential side C1 or the second circumferential side C2. In this example, the control device 20 determines that the wheel torque direction Ct is toward the first circumferential side C1 when the remainder when θ is divided by (360 / N) is within a range of 5±α [°]. In the example shown in FIGS. 5 to 7, the remainder when θ is divided by (360 / N) is 5 [°], which is within a range of 5±α [°]. Furthermore, the control device 20 determines that the wheel torque direction Ct is toward the second circumferential side C2 when the remainder when θ is divided by (360 / N) is within a range of 25±α [°]. In the example shown in FIGS. 8 to 10, the remainder when θ is divided by (360 / N) is 25 [°], which is within a range of 25±α [°]. Here, "α" is a value that is set in advance based on the error in the output value of the rotational position sensor 8 (including, for example, errors caused by the installation location of the rotational position sensor 8, errors caused by temperature, etc.).

[0077] FIG. 11 is a flowchart showing an example of the torque direction determination process and the unlocking assistance process performed by the control device 20.

[0078] As shown in Fig. 11, first, the control device 20 calculates the remainder when θ is divided by (360 / N) (step #1). Note that "r" in the formula shown in step #1 of Fig. 11 represents the remainder when θ is divided by (360 / N), and "mod" represents the operator of the remainder operation.

[0079] Next, the control device 20 determines whether the remainder (r) obtained by dividing θ by (360 / N) is within a specified range of r1±α (Step #2). If the remainder obtained by dividing θ by (360 / N) is within the specified range of r1±α (Step #2: Yes), the control device 20 determines that the wheel torque direction Ct is toward the first circumferential side C1 (Step #3). Note that, in the examples shown in FIGS. 5 to 7, each of r and r1 is 5°. r1 is set to, for example, half the rotatable range (angle range) of the target rotating member T (in this example, the first rotating member RT1) allowed by backlash in the locked state. When setting r1 in this way, if the rotatable range is 10°, r1 is set to 5°.

[0080] On the other hand, if the remainder (r) obtained by dividing θ by (360 / N) is not within the specified range of r1±α (Step #2: No), the control device 20 determines whether the remainder (r) obtained by dividing θ by (360 / N) is within the specified range of r2±α (Step #4). If the remainder (r) obtained by dividing θ by (360 / N) is within the specified range of r2±α (Step #4: Yes), the control device 20 determines that the wheel torque direction Ct is toward the second circumferential side C2 (Step #5). Note that, in the examples shown in FIGS. 8 to 10, r and r2 are each 25°. r2 is set to, for example, a value obtained by subtracting the set value of r1 from (360 / N).

[0081] The above steps #1 to #5 correspond to the torque direction determination process. After the torque direction determination process, the control device 20 executes the unlocking assistance process to cause the rotating electrical machine 1 to output torque in the opposite direction to the wheel torque direction Ct (step #6).

[0082] During the unlock assistance process, the control device 20 determines whether the detected rotational position has changed in a direction opposite to the direction of the deviation from the theoretical lock position P0 due to backlash (step #7). If the control device 20 detects that the detected rotational position has changed in a direction opposite to the direction of the deviation from the theoretical lock position P0 due to backlash (step #7: Yes), the control device 20 maintains or reduces the absolute value of the torque of the rotating electric machine 1 (step #8). For example, in the example shown in FIGS. 5 to 7, if the control device 20 detects that the detected rotational position has changed to the second circumferential side C2 during the unlock assistance process, the control device 20 maintains or reduces the absolute value of the torque of the rotating electric machine 1. On the other hand, if the control device 20 does not detect that the detected rotational position has changed in a direction opposite to the direction of the deviation from the theoretical lock position P0 due to backlash (step #7: No), the control device 20 returns to step #6 and continues the process.

[0083] According to this configuration, it is possible to avoid a situation in which the absolute value of the torque of the rotating electric machine 1 increases excessively during the unlock assistance process, which would in turn increase the engagement force between the lock member 4 and the first rotating member RT1, thereby preventing the movement of the lock member 4 from being hindered.

[0084] In this manner, in this embodiment, the direction along the rotation direction of the first rotating member RT1 is defined as the circumferential direction C, the first rotating member RT1 includes a plurality of second engaged portions Ta that are arranged in the circumferential direction C and engage with the second engaging portions 412 of the locking member 4; The detected rotation position is θ [°], and the number of second engaged portions Ta is N [units]. The control device 20 determines the wheel torque direction Ct based on the remainder obtained when θ is divided by (360 / N).

[0085] According to this configuration, the wheel torque direction Ct can be determined by a relatively simple calculation process.

[0086] As described above, the vehicle drive device 100 a rotating electric machine 1 that functions as a driving force source for wheels W; a parking lock mechanism 10 that selectively restricts rotation of a first rotating member RT1 that rotates in conjunction with the wheel W; a rotational position sensor 8 that detects the rotational position of a target rotating member T, the rotational position sensor 8 being configured to detect either a second rotating member RT2 that rotates in conjunction with the wheel W and is disposed closer to the wheel W than the first rotating member RT1 in a power transmission path that connects the rotating electric machine 1 and the wheel W, or the first rotating member RT1; A vehicle drive device (100) including a control device (20) that acquires a detection value of a rotational position sensor (8) and controls a rotating electric machine (1) and a parking lock mechanism (10), The parking lock mechanism 10 includes a locking member 4 that is movable between a locked position P1 where the locking member 4 engages with a first rotating member RT1 to restrict rotation of the first rotating member RT1 and an unlocked position P2 where the locking member 4 is separated from the first rotating member RT1 to allow rotation of the first rotating member RT1, and a drive device 5 that drives the locking member 4. There is a backlash in the rotational direction between the locking member 4 at the locking position P1 and the first rotating member RT1, The state of the parking lock mechanism 10 when the lock member 4 is in the lock position P1 is defined as a locked state, the rotational position of the target rotating member T detected by the rotational position sensor 8 in the locked state is defined as a detected rotational position, and the rotational position of the target rotating member T in the locked state when no backlash exists is defined as a theoretical locked position P0. The control device 20 executes a torque direction determination process to determine the wheel torque direction Ct, which is the direction of the torque being transmitted from the wheel W to the first rotating member RT1, based on the direction of deviation of the detected rotational position from the theoretical lock position P0 due to backlash.

[0087] According to this configuration, in the torque direction determination process, the wheel torque direction Ct is determined based on the direction of deviation of the detected rotational position from the theoretical lock position P0 due to backlash. This makes it possible to appropriately output to the rotating electric machine 1 a torque in a direction that weakens the engagement force between the lock member 4 and the first rotating member RT1. Therefore, when unlocking the parking lock mechanism 10, the torque of the rotating electric machine 1 can be appropriately controlled. In this way, even if the lock member 4 cannot be moved from the locked position P1 toward the unlocked position P2 by the driving force of the drive unit 5, the engagement force between the lock member 4 and the first rotating member RT1 can be weakened using the torque of the rotating electric machine 1, so that the parking lock mechanism 10 can be unlocked by the driving force of the drive unit 5. Furthermore, this configuration eliminates the need for various sensors such as a tilt angle sensor for determining the wheel torque direction Ct, which makes it easier to simplify the configuration of the vehicle drive device 100 and reduce costs.

[0088] Furthermore, as described above, in this embodiment, when the drive unit 5 generates a driving force to move the locking member 4 from the locked position P1 to the unlocked position P2, the control unit 20 executes an unlock assist process to output a torque to the rotating electric machine 1 in the opposite direction to the wheel torque direction Ct.

[0089] According to this configuration, in the unlocking assistance process, it is possible to cause the rotating electrical machine 1 to appropriately output torque in a direction that weakens the engagement force between the locking member 4 and the first rotating member RT1.

[0090] In this embodiment, the backlash is set to be larger than the error in the output value of rotational position sensor 8. The error in the output value of rotational position sensor 8 may be caused by, for example, the installation location of rotational position sensor 8, temperature, etc., and can be determined in advance by experiment, etc.

[0091] According to this configuration, it is easy to avoid erroneous determination of the wheel torque direction Ct due to an error in the output value of the rotational position sensor 8.

[0092] Other Embodiments (1) In the above embodiment, the first rotating member RT1 is the rotor shaft 12b. However, the present invention is not limited to such a configuration. For example, the first rotating member RT1 may be the carrier CR. Alternatively, the first rotating member RT1 may not be the rotating member itself that constitutes the power transmission path connecting the rotating electric machine 1 and the wheels W, but may be a parking gear connected to the rotating member.

[0093] (2) In the above embodiment, an example has been described in which the first rotating member RT1 is the target rotating member T. However, the present invention is not limited to such a configuration, and the second rotating member RT2 may be the target rotating member T. In this case, since the first gear 22 is the second rotating member RT2 in the above embodiment, the first gear 22 is the target rotating member T. A rotational position sensor for detecting the rotational position of the first gear 22 may be provided separately from the rotational position sensor 8.

[0094] (3) In the above embodiment, the drive device 5 moves the locking member 4 from the locked position P1 to the unlocked position P2 by electromagnetic force. However, the present invention is not limited to such a configuration. For example, the locking member 4 may be moved from the locked position P1 to the unlocked position P2 by the driving force of an electric motor.

[0095] (4) In the above embodiment, the number of second engaged parts Ta is 12 (N=12), but the present invention is not limited to such a configuration. If the rotational position sensor 8 is a resolver, the number of second engaged parts Ta is preferably an integer multiple of the number of poles of the resolver. For example, if the resolver has four poles, the number of second engaged parts Ta is preferably 12, 8, 16, 20, etc.

[0096] (5) The configurations disclosed in the above-described embodiments can be applied in combination with configurations disclosed in other embodiments, as long as no contradictions arise. Regarding other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be made as appropriate within the scope of the present disclosure.

[0097] [Summary of this embodiment] The vehicle drive device (100) described above will now be outlined.

[0098] The vehicle drive device (100) includes: a rotating electric machine (1) that functions as a driving force source for wheels (W); a parking lock mechanism (10) that selectively restricts rotation of a first rotating member (RT1) that rotates in conjunction with the wheel (W); a rotational position sensor (8) that detects the rotational position of a target rotating member (T), the rotational position sensor (8) being configured to detect ... a control device (20) that acquires a detection value of the rotational position sensor (8) and controls the rotating electric machine (1) and the parking lock mechanism (10), The parking lock mechanism (10) includes a locking member (4) that is movable between a locking position (P1) that engages with the first rotating member (RT1) to restrict rotation of the first rotating member (RT1) and an unlocking position (P2) that is separated from the first rotating member (RT1) to allow rotation of the first rotating member (RT1), and a driving device (5) that drives the locking member (4), There is a backlash in the rotational direction between the locking member (4) at the locking position (P1) and the first rotating member (RT1), The state of the parking lock mechanism (10) when the lock member (4) is in the lock position (P1) is defined as a locked state, the rotational position of the target rotating member (T) detected by the rotational position sensor (8) in the locked state is defined as a detected rotational position, and the rotational position of the target rotating member (T) in the locked state when there is no backlash is defined as a theoretical locked position (P0), The control device (20) executes a torque direction determination process to determine the wheel torque direction (Ct), which is the direction of the torque being transmitted from the wheel (W) to the first rotating member (RT1), based on the direction of deviation of the detected rotational position from the theoretical lock position (P0) due to the backlash.

[0099] According to this configuration, in the torque direction determination process, the wheel torque direction (Ct) is determined based on the direction of deviation of the detected rotational position from the theoretical lock position (P0) due to backlash. This allows the rotating electric machine (1) to appropriately output torque in a direction that weakens the engagement force between the lock member (4) and the first rotating member (RT1). Therefore, when unlocking the parking lock mechanism (10), the torque of the rotating electric machine (1) can be appropriately controlled. Thus, even when the lock member (4) cannot be moved from the locked position (P1) toward the unlocked position (P2) by the driving force of the drive device (5), the torque of the rotating electric machine (1) can be weakened by the torque of the rotating electric machine (1). Therefore, the parking lock mechanism (10) can be unlocked by the driving force of the drive device (5). Furthermore, this configuration eliminates the need for various sensors, such as a tilt angle sensor, for determining the wheel torque direction (Ct), which facilitates the simplification and cost reduction of the configuration of the vehicle drive device (100).

[0100] Here, when the drive device (5) generates a driving force for moving the locking member (4) from the locked position (P1) to the unlocked position (P2), the control device (20) preferably executes an unlock assist process for outputting a torque to the rotating electric machine (1) in a direction opposite to the wheel torque direction (Ct).

[0101] According to this configuration, in the unlocking assistance process, it is possible to cause the rotating electric machine (1) to appropriately output torque in a direction that weakens the engagement force between the locking member (4) and the first rotating member (RT1).

[0102] In addition, the direction along the rotation direction of the first rotating member (RT1) is defined as a circumferential direction (C), the first rotating member (RT1) includes a plurality of engaged portions (Ta) that are arranged in the circumferential direction (C) and engage with engaging portions (412) of the locking member (4); The detected rotation position is θ [°], and the number of the engaged portions (Ta) is N [pieces]. It is preferable that the control device (20) determines the wheel torque direction (Ct) based on the remainder obtained when θ is divided by (360 / N).

[0103] According to this configuration, the wheel torque direction (Ct) can be determined by a relatively simple calculation process.

[0104] In the above configuration, it is preferable that the backlash is set to be larger than the error in the output value of the rotational position sensor (8).

[0105] This configuration makes it easy to avoid erroneous determination of the wheel torque direction (Ct) due to an error in the output value of the rotational position sensor (8).

[0106] In the above configuration, it is preferable that the rotational position sensor (8) is set so that the detected value of the rotational position of the target rotating member (T) becomes zero at one of the N theoretical lock positions (P0).

[0107] According to this configuration, the calculation process for determining the wheel torque direction (Ct) can be simplified.

[0108] In the above configuration, it is preferable that the control device (20) maintains or reduces the absolute value of the torque of the rotating electric machine (1) when it detects, during the unlocking assistance process, that the detected rotational position has changed in a direction opposite to the direction of the deviation from the theoretical lock position (P0) caused by the backlash.

[0109] According to this configuration, it is possible to avoid a situation in which the absolute value of the torque of the rotating electric machine (1) increases excessively during the unlocking assistance process, which would result in an increase in the engagement force between the locking member (4) and the first rotating member (RT1), thereby preventing the movement of the locking member (4). [Industrial Applicability]

[0110] The technology disclosed herein can be used in a vehicle drive device that includes a rotating electric machine that functions as a driving force source for wheels, and a parking lock mechanism that selectively restricts the rotation of a rotating member that rotates in conjunction with the wheels. [Explanation of symbols]

[0111] 100: Vehicle drive device, 1: Rotating electric machine, 4: Locking member, 412: Second engaging portion (engaging portion), 5: Drive device, 8: Rotational position sensor, 10: Parking lock mechanism, 20: Control device, RT1: First rotating member, RT2: Second rotating member, T: Target rotating member, Ta: Second engaged portion (engaged portion), W: Wheel, P0: Theoretical lock position, P1: Lock position, P2: Unlock position, C: Circumferential direction, Ct: Wheel torque direction

Claims

1. a rotating electric machine that functions as a driving force source for the wheels; a parking lock mechanism that selectively restricts rotation of a first rotating member that rotates in conjunction with the wheels; a second rotating member that rotates in conjunction with the wheel and is disposed closer to the wheel than the first rotating member in a power transmission path that connects the rotating electric machine and the wheel; and a rotational position sensor that detects the rotational position of either the first rotating member or the second rotating member as a target rotating member; a control device that acquires a detection value of the rotational position sensor and controls the rotating electric machine and the parking lock mechanism, the parking lock mechanism includes a locking member that is movable between a locked position where the locking member engages with the first rotating member to restrict rotation of the first rotating member and an unlocked position where the locking member is separated from the first rotating member to allow rotation of the first rotating member; and a drive device that drives the locking member, a backlash in a rotational direction exists between the locking member in the locked position and the first rotating member, The state of the parking lock mechanism when the locking member is in the locked position is defined as a locked state, the rotational position of the target rotating member detected by the rotational position sensor in the locked state is defined as a detected rotational position, and the rotational position of the target rotating member in the locked state when no backlash exists is defined as a theoretical locked position, The control device executes a torque direction determination process to determine a wheel torque direction, which is the direction of torque being transmitted from the wheel to the first rotating member, based on a direction of deviation of the detected rotational position from the theoretical lock position due to the backlash.

2. 2. The vehicle drive device according to claim 1, wherein the control device executes an unlock assist process to cause the rotating electric machine to output torque in a direction opposite to a wheel torque direction when the drive device generates a driving force for moving the locking member from the locked position to the unlocked position.

3. a direction along the rotation direction of the first rotating member being a circumferential direction, the first rotating member includes a plurality of engaged portions that are arranged in the circumferential direction and engage with the engaging portions of the locking member, The detected rotational position is θ [°], and the number of the engaged portions is N [pieces].

3. The vehicle drive system according to claim 1, wherein the control device determines the wheel torque direction based on a remainder obtained when θ is divided by (360 / N).

4. 4. The vehicle drive device according to claim 3, wherein the backlash is set to be larger than an error in the output value of the rotational position sensor.

5. 4. The vehicle drive device according to claim 3, wherein the rotational position sensor is set so that a detected value of the rotational position of the target rotating member becomes zero at one of the N theoretical lock positions.

6. 3. The vehicle drive device according to claim 2, wherein the control device maintains or reduces the absolute value of the torque of the rotating electric machine when it detects, during the unlocking assistance process, that the detected rotational position has changed in a direction opposite to a direction of deviation from the theoretical lock position due to the backlash.

Images