JP2022121168A - parking lock system - Google Patents

Abstract

To provide a parking lock system which can properly unlock a parking lock in a vehicle inclined state.SOLUTION: A main machine motor 70 is a driving source of a vehicle. A parking lock mechanism 30 has a parking lever which may engage with a parking gear 35 connected to an axle 95. The parking gear 35 and the parking lever engage with each other to lock rotation of the axle 95. A motor may drive the parking lever. A control unit 80 has an MG control unit 85 and an actuator control unit 81. When a lock state of the parking lock mechanism 30 is unlocked in a state that the vehicle is inclined, the MG control unit 85 controls the main machine motor 70 so as to reduce an engagement load between the parking gear 35 and the parking lever. The actuator control unit 81 controls the motor so as to unlock the lock state after standing by for torque generation of the main machine motor 70.SELECTED DRAWING: Figure 1

Description

The present invention relates to parking lock systems.

2. Description of the Related Art Conventionally, an electric vehicle is known that includes an electric motor as a drive source when the vehicle is running. For example, in Patent Document 1, when a shift lever is to be operated for a P-less shift operation, an electric motor is operated so that the meshing load becomes approximately 0 in accordance with the inclination angle of the vehicle. Reduced load.

JP-A-9-286312

When supplementing the P-release torque of the parking lock mechanism with an electric motor for traveling (hereinafter referred to as the "main motor"), for example, the torque applied to the parking gear is reduced due to a delay in the rise of the main motor's torque, etc., due to the tilting of the vehicle. If the parking lock is disengaged in a state where it has not been canceled, there is a risk that the torsion component will swing back.

SUMMARY OF THE INVENTION An object of the present invention is to provide a parking lock system capable of appropriately releasing the parking lock when the vehicle is tilted.

The parking lock system of the present invention includes a main motor (70), a parking lock mechanism (30), an actuator (50), and a controller (80). The main motor is the drive source of the vehicle (100). The parking lock mechanism has a parking lever (33) that can be engaged with a parking gear (35) connected to an axle (95), and engagement of the parking gear and the parking lever can lock rotation of the axle. . The actuator can drive the parking lever. The control section has a main motor control section (85) that controls the main motor, and an actuator control section (81) that controls the actuator.

When releasing the locked state of the parking lock mechanism in a state where the vehicle is tilted, the main machine motor control section controls the main machine motor so as to reduce the meshing load between the parking gear and the parking lever. The actuator control unit controls the actuator so that the locked state is released after waiting for the main motor to generate torque. As a result, the parking lock can be appropriately released when the vehicle is tilted.

1 is a schematic configuration diagram showing a vehicle drive system according to a first embodiment; FIG. 4 is a perspective view illustrating a shift range switching mechanism and a parking lock mechanism according to the first embodiment; FIG. 1 is a cross-sectional view showing a rotary actuator according to a first embodiment; FIG. 4 is a view in the direction of arrow VI in FIG. 3; FIG. 4 is a view in the direction of arrow V in FIG. 3; FIG. It is an explanatory view explaining a state where vehicles are leaning. It is an explanatory view explaining the torque required for P removal. FIG. 4 is an explanatory diagram for explaining load received from wheels and MG torque; FIG. 4 is an explanatory diagram for explaining load received from wheels and MG torque; 4 is a flowchart for explaining MG control processing according to the first embodiment; 4 is a flowchart for explaining actuator control processing according to the first embodiment; 4 is a time chart for explaining notP switching processing according to the first embodiment; FIG. 4 is an explanatory diagram for explaining the drive state of the shift range switching mechanism according to the first embodiment; 9 is a flowchart for explaining actuator control processing according to the second embodiment; 9 is a time chart for explaining notP switching processing according to the second embodiment; FIG. 10 is an explanatory diagram for explaining the drive state of the shift range switching mechanism according to the second embodiment; FIG. 11 is a flowchart for explaining actuator control processing according to the third embodiment; FIG. FIG. 11 is a time chart for explaining notP switching processing according to the third embodiment; FIG. FIG. 11 is an explanatory diagram for explaining the driving state of the shift range switching mechanism according to the third embodiment; FIG. 14 is a flowchart for explaining actuator control processing according to the fourth embodiment; FIG. FIG. 16 is a flowchart for explaining actuator control processing according to the fifth embodiment; FIG. FIG. 14 is a time chart for explaining notP switching processing according to the fifth embodiment; FIG. FIG. 14 is a flowchart for explaining actuator control processing according to the sixth embodiment; FIG. FIG. 14 is a time chart for explaining notP switching processing according to the seventh embodiment; FIG. FIG. 21 is a perspective view showing a parking lock mechanism according to an eighth embodiment;

A parking lock system according to the present invention will now be described with reference to the drawings. Hereinafter, in a plurality of embodiments, substantially the same configurations are denoted by the same reference numerals, and descriptions thereof are omitted.

(First embodiment)
A first embodiment will be described with reference to FIGS. 1 to 13. FIG. As shown in FIG. 1, a vehicle drive system 90 as a parking lock system includes a main motor 70, an inverter 71, a parking lock mechanism 30, a rotary actuator 40, a control unit 80, and the like. ). In the figure, the main machine motor 70 is appropriately described as "MG".

The main motor 70 functions as an electric motor that generates torque by being rotated by being supplied with electric power from a battery (not shown) via an inverter 71, and functions as a generator that is driven and generates power when the vehicle 100 is braked. is a so-called motor generator. In the figure, the main machine motor 70 is appropriately described as "MG". The driving force generated by the main machine motor 70 rotates the wheels 98 via the reduction gear 72 and the axle 95 . FIG. 1 shows an example of an electric vehicle in which the drive source of the vehicle 100 is the main motor 70, but the vehicle 100 may be a hybrid vehicle that also has an engine (not shown) as the drive source. In FIG. 1, for the sake of explanation, the parking gear 35 is shown separately from the parking lock mechanism 30, and the shift range switching mechanism 20 is omitted.

As shown in FIG. 2 , parking lock mechanism 30 and rotary actuator 40 constitute shift-by-wire system 1 . The shift-by-wire system 1 includes a rotary actuator 40, a shift range switching mechanism 20, a parking lock mechanism 30, and the like. The rotary actuator 40 is composed of a motor 50 and a power transmission section 510 (see FIG. 3, etc.).

The motor 50 is a DC motor with brushes, and rotates when power is supplied from a battery mounted on the vehicle 100 (see FIG. 6) via a drive circuit such as an H bridge circuit to shift the shift range. It functions as a drive source for the switching mechanism 20 . A shift range switching mechanism 20 , which is a detent mechanism, has a detent plate 21 , a detent spring 25 and the like, and transmits rotational driving force output from the motor 50 to the parking lock mechanism 30 .

The detent plate 21 is fixed to the output shaft 15 and driven by the motor 50 . On the detent spring 25 side of the detent plate 21, two troughs 211 and 212 and a peak 215 separating the troughs 211 and 212 are provided. Wall portions 217 and 218 are formed on both sides of the valley portions 211 and 212 to restrict the movement of the detent roller 26 (see FIG. 13 and the like). Hereinafter, the wall portion 217 on the P range side is referred to as "P wall", the valley portion 211 is referred to as "P valley", the valley portion 212 on the notP range side is referred to as "notP valley", and the wall portion 218 is referred to as "notP wall".

The detent spring 25 is an elastically deformable plate-shaped member, and has a detent roller 26 at its tip. The detent spring 25 urges the detent roller 26 toward the rotation center of the detent plate 21 . The positions where the detent rollers 26 are dropped by the spring force of the detent springs 25 in the no-load state are the bottommost portions of the valleys 211 and 212 .

When a rotational force greater than or equal to a predetermined amount is applied to the detent plate 21 , the detent spring 25 is elastically deformed and the detent roller 26 moves between the troughs 211 and 212 . By fitting the detent roller 26 into one of the troughs 211 and 212, the swinging of the detent plate 21 is restricted, the state of the parking lock mechanism 30 is determined, and the shift range is fixed.

The parking lock mechanism 30 has a parking rod 31 , a cone 32 , a parking lock pole 33 , a shaft portion 34 and a parking gear 35 . The parking rod 31 is formed in a substantially L shape, and one end 311 side is fixed to the detent plate 21 . A cone 32 is provided on the other end 312 side of the parking rod 31 . The conical body 32 is formed so as to decrease in diameter toward the other end 312 side. When the detent plate 21 rotates in the direction in which the detent roller 26 fits into the valley portion 211 corresponding to the P range, the cone 32 moves in the arrow P direction.

The parking lock pole 33 abuts on the conical surface of the conical body 32 and is provided swingably about the shaft portion 34 . A protrusion 331 that can mesh with the parking gear 35 is provided on the parking lock pole 33 on the side of the parking gear 35 . When the conical body 32 moves in the direction of arrow P due to the rotation of the detent plate 21 , the parking lock pole 33 is pushed up, and the protrusion 331 and the parking gear 35 are meshed. On the other hand, when the cone 32 moves in the direction of the arrow notP, the projection 331 and the parking gear 35 are disengaged.

The parking gear 35 is connected to the axle 95 via the reduction gear set 96 (see FIG. 1), and is provided so as to be able to mesh with the convex portion 331 of the parking lock pole 33 . When the parking gear 35 and the convex portion 331 are engaged with each other, the rotation of the axle is restricted. When the shift range is not P, which is a range other than P, parking gear 35 is not locked by parking lock pole 33 and rotation of axle 95 is not prevented by parking lock mechanism 30 . Also, when the shift range is in the P range, the parking gear 35 is locked by the parking lock pole 33 and the rotation of the axle 95 is restricted.

A rotary actuator 40 is shown in FIGS. FIG. 3 is a cross-sectional view taken along line III--III in FIG. In FIG. 3, the axial direction of the motor 50 is defined as the vertical direction of the paper, the upper side of the paper is defined as "one side", and the lower side of the paper is defined as the "other side".

The housing 41 is made of metal such as aluminum, and is composed of a motor housing portion 411 and a gear housing portion 412 . The motor housing portion 411 is formed in a substantially bottomed cylindrical shape that is open on one side in the axial direction. The gear housing portion 412 is formed to protrude radially outward from the motor housing portion 411 . One end face of the gear housing portion 412 is formed substantially flush with one end face of the motor housing portion 411 . The other end face of the gear housing portion 412 is located in the axial middle of the motor housing portion 411 . In other words, the motor housing portion 411 protrudes to the other side. An output shaft gear housing portion 413 for housing the output shaft gear 60 is formed in the gear housing portion 412 so as to protrude in the opposite direction to the motor housing portion 411 .

The sensor cover 43 and gear cover 45 are provided on both sides of the housing 41 . Sensor cover 43 is provided on one side of motor housing portion 411 and gear housing portion 412 and fixed to housing 41 with screws 439 . A connector 435 is provided on the sensor cover 43 , and power is supplied to the rotary actuator 40 via the connector 435 . It also transmits and receives signals to and from the outside via the connector 435 . The gear cover 45 is provided on the other side of the gear housing portion 412 and fixed to the housing 41 with screws 459 .

The motor 50 has a magnet 501, a core 502, a coil 504, a motor shaft 505, a commutator 508, and brushes (not shown). Magnet 501 is fixed to the inner peripheral side of motor housing portion 411 . The core 502 is provided inside the magnet 501 in the radial direction, and generates a rotational force when current flows through the coil 504 wound around the core 502 . A motor shaft 505 is rotatably supported by bearings 506 and 507 and rotates together with the core 502 . The commutator 508 causes the current supplied from the brush to flow through the coil 504 .

The power transmission portion 510 is provided between the motor shaft 505 and the output shaft 15 and transmits the driving force of the motor 50 to the output shaft 15 . The power transmission section 510 has gears 51 to 54 and 60 . Gears 51 to 54 and 60 are all spur gears.

The motor gear 51 and the gears 52 and 53 are arranged in a first gear chamber 415 that opens to one side of the housing 41 . The gear 54 and the output shaft gear 60 are arranged in a second gear chamber 416 that opens on the other side of the housing 41 . The first gear chamber 415 and the second gear chamber 416 communicate with each other through a shaft hole 417 through which the gear connection shaft 55 is inserted. In this embodiment, the motor gear 51, the gear 54 and the output shaft gear 60 are made of metal, and the gears 52 and 53 are made of resin.

The motor gear 51 is fixed to one side of the motor shaft 505 and rotates together with the motor shaft 505 . Gear 52 has a large diameter portion 521 and a small diameter portion 522 and rotates together with shaft 525 . A spur tooth is formed on the radially outer side of the large diameter portion 521 and meshes with the motor gear 51 . A spur tooth is formed on the radially outer side of the small diameter portion 522 and meshes with the gear 53 . The shaft 525 is inserted into an axial hole 414 formed in the housing 41 and rotatably supported.

The gear 53 has a tubular portion 531 and a gear portion 532 . The gear portion 532 is formed to protrude radially outward from the cylindrical portion 531 . The gear portion 532 is formed with spur teeth that mesh with the small diameter portion 522 of the gear 52 . The gear portion 532 is formed within a range (for example, less than 180°) in which the absolute angle can be detected by the rotation angle sensor 68 . A shaft fixing member 535 is provided radially inside the cylindrical portion 531 . The shaft fixing member 535 is made of metal, for example.

The gear connection shaft 55 is rotatably supported in the housing 41 by bearings 56 and 57 . In this embodiment, the bearings 56 and 57 are ball bearings and are press-fitted into the shaft hole 417 . By providing a plurality of bearings, tilting of the gear connection shaft 55 can be suppressed. In addition, since rattling in the radial direction of the gear connection shaft 55 can be suppressed, it is possible to reduce the occurrence of wear due to hitting of the shaft or the like.

One side of the gear connection shaft 55 is press-fitted into a shaft fixing member 535 provided radially inwardly of the cylindrical portion 531 of the gear 53 and fixed by, for example, rolling caulking. Thereby, the gear 53 is fixed to one side of the gear connection shaft 55 . A gear 54 is fixed to the other side of the gear connection shaft 55 with a bolt 549 . As a result, the cylindrical portion 351 of the gear 53 and the gear 54 are coaxially connected by the gear connection shaft 55 and rotate together. In this embodiment, the gear 53 and the gear 54 constitute a coupling gear 530 . The gear 54 is formed to have substantially the same diameter as the cylindrical portion 531 , and has spur teeth that mesh with the output shaft gear 60 on the entire outer periphery in the radial direction.

The output shaft gear 60 has an output shaft connection portion 601 and a gear portion 602 formed in a substantially cylindrical shape. The output shaft connecting portion 601 is rotatably supported on the gear cover 45 by a bush 61 provided radially outward. The output shaft 15 (see FIG. 1) is press-fitted inside the output shaft connecting portion 601 in the radial direction, and rotates integrally. The bushing 61 is press-fitted into the output shaft holding portion 455 of the gear cover 45 .

The gear portion 602 is formed to protrude radially outward of the output shaft connecting portion 601 and meshes with the gear 54 . In this embodiment, the meshing point between the motor gear 51 and the large diameter portion 521 of the gear 52 is the first speed reduction stage, and the meshing point between the small diameter portion 522 of the gear 52 and the gear portion 532 of the gear 53 is the second speed reduction stage. A portion of meshing between the gear 54 and the gear portion 602 of the output shaft gear 60 is the third speed reduction stage. That is, in this embodiment, the number of reduction stages is three, and the third reduction stage is the final reduction stage.

Gears 52 , 53 and the like are assembled from one side of housing 41 , and gear 54 and output shaft gear 60 and the like are assembled from the other side of housing 41 . By changing the length of the gear connection shaft 55 that connects the gear 53 and the gear 54, the protruding margin of the motor housing portion 411 is adjusted in accordance with the mating component assembled via the rotary actuator 40 and the output shaft 15. can do. As a result, the degree of freedom in mounting can be improved.

A sensor magnet 65 is provided radially inside the cylindrical portion 531 of the gear 53 and closer to the sensor cover 43 than the shaft fixing member 535 . The sensor magnet 65 is formed in a narrow plate shape, for example, and is provided on the opposite side of the gear 53 with the rotating shaft interposed therebetween. In other words, the sensor magnets 65 are provided 180 degrees apart. The sensor magnet 65 is held by a magnet holding member 66 formed in an annular shape. The magnet holding member 66 is fixed to the cylindrical portion 531 by press fitting or the like.

The rotation angle sensor 68 is held by a sensor holding portion 438 that protrudes from the sensor cover 43 . The rotation angle sensor 68 has a Hall IC that detects changes in the magnetic field due to the rotation of the sensor magnets 65 , and is provided so that the sensor element is positioned at the center of the two sensor magnets 65 . In this embodiment, since the reduction ratio of the final reduction stage is 6 or less and the rotation range of the gear 53 is less than 180°, the rotation angle sensor 68 can detect the rotation position of the gear 53 as an absolute angle. . Further, the absolute angle of the output shaft 15 can be calculated by gear ratio conversion.

The gear 53 provided with the sensor magnet 65 constitutes a speed reduction stage one step before the final speed reduction stage. Therefore, the transmission torque is smaller than that of the output shaft gear 60, and the eccentric force generated by variations in the shape of the gear tooth surface and vibration is small. Accuracy deterioration can be suppressed.

As shown in FIG. 1, the control unit 80 is mainly composed of a microcomputer or the like, and is equipped with a CPU, ROM, RAM, I/O (none of which are shown), bus lines connecting these components, and the like. ing. Each process in the control unit 80 may be software processing by executing a program stored in advance in a substantial memory device such as a ROM (that is, a readable non-temporary tangible recording medium) by the CPU, It may be hardware processing by a dedicated electronic circuit.

The control unit 80 has an actuator control unit 81, an MG control unit 85, etc. as functional blocks. The actuator control unit 81 controls energization of the motor 50 , and the MG control unit 85 controls energization of the main motor 70 . Here, the actuator control unit 81 and the MG control unit 85 are provided in one control unit 80, but the motor ECU that controls the motor 50 and the MG-ECU that controls the main motor 70 may be separated. .

The control unit 80 controls the switching of the shift range by controlling the drive of the motor 50 based on the shift range requested by the driver, the signal from the brake switch, the vehicle speed, and the like. Further, the oil temperature of the transmission 7 connected to the shift range switching mechanism 20 (hereinafter referred to as "TM oil temperature") or the like may be used to control the energization of the coil 504. FIG. The transmission 7 may be a transaxle or the like.

As described above, in the shift-by-wire system 1, driving the motor 50 releases the parking lock. As shown in FIG. 6, when the vehicle 100 is stopped in an inclined state, a load L (see formula (1)) corresponding to the vehicle weight W and the inclination angle θ is applied in the longitudinal direction of the vehicle 100 . , this load L generates a torsional torque of the axle 95 and a meshing load between the parking gear 35 and the parking lock pole 33 .

L=W×sin θ (1)

Therefore, when the vehicle 100 is in a tilted state, pulling out the parking lock pole 33 from the parking gear 35 requires a larger torque than when the vehicle is on a flat road due to the meshing load described above. Hereinafter, pulling out the projection 331 of the parking lock pole 33 from the parking gear 35 will be referred to as "P removal" as appropriate.

Specifically, as shown in FIG. 7 , when the vehicle 100 is tilted, when the P release is performed, in addition to the torque for switching the detent of the shift range switching mechanism 20 indicated by the solid line, the vehicle weight indicated by the dashed line is added. A torque corresponding to the load L corresponding to W and the inclination angle θ is required. When the torque for the load L is provided by the motor 50, the size of the motor 50 is increased.

Therefore, as shown in FIGS. 8 and 9, the main motor 70 is driven to generate a torque (hereinafter referred to as "cancellation torque" as appropriate) that cancels the load L applied to the axle 95 due to the tilt of the vehicle. For example, positive torque is generated when the vehicle 100 is on an upward slope, and negative torque is generated when the vehicle is on a downward slope. As a result, the torque required for the motor 50 can be reduced and the size of the motor 50 can be reduced as compared with the case where the P removal is performed using only the torque of the motor 50 . In addition, the amount of energization and heat load of a drive circuit (not shown) for driving the motor 50 can be reduced.

In this embodiment, the maximum torque that can be output from the motor 50 can be pulled out when the axle 95 is not loaded, and when the axle 95 is loaded by a steep tilt of the vehicle 100, Make it impossible to remove P. In practice, the output torque from the motor 50 is set with a margin with respect to the torque required to remove P when no load is applied. , and the main motor 70 outputs a torque according to the load L.

MG control processing of this embodiment will be described based on the flowchart of FIG. This process is executed by the control unit 80 at a predetermined cycle. Hereinafter, the “step” of step S501 will be omitted and simply denoted by the symbol “S”. Other steps are similar.

In S501, the MG control unit 85 determines whether or not there is a notP switching request. If it is determined that there is no notP switching request (S501: NO), the process after S502 is skipped. If it is determined that there is a notP switching request (S501: YES), the process proceeds to S502.

In S502, the MG control unit 85 determines whether or not the absolute value of the tilt angle θ of the vehicle 100 is greater than the tilt determination threshold value θth. If it is determined that the absolute value of the tilt angle θ is equal to or less than the tilt determination threshold value θth (S502: NO), the processing after S503 is skipped. If it is determined that the absolute value of the tilt angle θ is greater than the tilt determination threshold value θth (S502: YES), the process proceeds to S503.

In S503, the MG control unit 85 controls the main motor 70 and applies torque to the axle 95 so that the output torque becomes the MG torque target value Ttgt. The MG torque target value Ttgt may be a predetermined value according to the vehicle weight W, or may be a value set according to the inclination angle θ. Hereinafter, the output torque of the main motor 70 will be referred to as "MG torque Tmg" as appropriate.

In S504, the MG control unit 85 determines whether or not the notP switching has been completed. Here, when the detent roller 26 reaches the notP range based on the detection value of the rotation angle sensor 68, it is determined that the notP switching has been completed. If it is determined that the notP switching has not been completed (S504: NO), the process returns to S503 to continue torque application. If it is determined that the notP switching has been completed (S504: YES), the process proceeds to S505, energization to the main motor 70 is turned off, and the MG torque Tmg is set to zero.

In this embodiment, the main motor 70 is turned off when the notP switching is completed. , can be arbitrarily set after the parking lock is released.

The actuator control processing of this embodiment will be described based on the flowchart of FIG. This process is executed by the control unit 80 at a predetermined cycle. S101 is the same as S501, and the actuator control unit 81 determines whether or not there is a notP switching request. If it is determined that there is no notP request (S101: NO), the process after S102 is skipped. If it is determined that there is a notP request (S101: YES), the process proceeds to S102.

In S102, the actuator control unit 81 controls the energization of the motor 50 so that the target value of the rotation angle sensor 68 is the notP valley and the detection value of the rotation angle sensor 68 becomes the target value. The current target value for energizing the motor 50 is stagnant at a position where the convex portion 331 of the parking lock pole 33 does not come out of the parking gear 35 until the main motor 70 generates torque that cancels the torque due to the load L. It is set to a value of degree. The current target value may be a predetermined value, or may be set according to the tilt angle θ.

In S103, the actuator control section 81 determines whether or not the detection value of the rotation angle sensor 68 has reached the target value. It is determined whether or not the detected value of the rotation angle sensor 68 has reached the target value. If it is determined that the detected value of the rotation angle sensor 68 has not reached the target value (S103: NO), the process returns to S102 to continue control of power supply to the motor 50. FIG. If it is determined that the detected value of the rotation angle sensor 68 has reached the target value (S103: YES), the process proceeds to S104, and power supply to the motor 50 is turned off.

The notP switching process of this embodiment will be described based on the time chart of FIG. In FIG. 12 , from the top, the shift instruction, the MG torque command value, the output torque of the main motor 70 (hereinafter referred to as “MG torque”), the target value of the rotation angle sensor 68, the detection value of the rotation angle sensor 68, the motor 50 motor current. For the sake of explanation, the target value and detected value of the rotation angle sensor 68 are described corresponding to the position of the detent roller 26, for example, "P valley" is the value when the detent roller 26 is positioned at the P valley. did. The time chart shows an example in which the vehicle 100 is on an upward slope and the main motor 70 outputs positive torque as cancel torque. When the vehicle 100 slopes downward, the main motor 70 outputs negative torque as cancel torque. The same applies to time charts according to embodiments described later.

At time x10, when the vehicle 100 is stopped on a slope with an inclination angle θ greater than the inclination determination threshold value θth and a notP switching request is input, the MG torque target value Ttgt is set and the main motor 70 is driven. Also, the target value of the rotation angle sensor 68 is set to the notP valley, and the motor 50 is driven. In this embodiment, the motor 50 is driven so as to output a torque sufficient to remove P on a flat road. Due to insufficient torque, the output shaft 15 stagnates in a state in which the parking lock pole 33 is not removed from the parking gear 35 (see FIG. 13). In FIG. 13, the times corresponding to the time charts are shown in angle brackets. The same applies to FIG. 16 and the like according to embodiments described later.

At time x12, when the MG torque reaches a value T1 that can cancel the torque due to the load L, the stagnation of the output shaft 15 is eliminated and the output shaft 15 starts to move. At time x13, when the MG torque reaches the MG torque target value Ttgt, the output torque at this time is maintained.

When the detent roller 26 reaches the notP range at time x14, the MG torque command value is set to 0, and the main motor 70 stops at time x16. At time x15 when the detected value of the rotation angle sensor 68 reaches the target value, the power to the motor 50 is turned off.

As described above, the vehicle drive system 90 of this embodiment includes the main motor 70 , the parking lock mechanism 30 , the motor 50 and the control section 80 . Main motor 70 is a drive source for vehicle 100 . The parking lock mechanism 30 has a parking lock pole 33 that can be meshed with a parking gear 35 connected to an axle 95. The parking gear 35 and the parking lock pole 33 are meshed to lock the rotation of the axle 95. . Motor 50 can drive parking lock pole 33 . In this embodiment, the motor 50 drives the parking lock mechanism 30 via the shift range switching mechanism 20 . The control unit 80 has an MG control unit 85 that controls driving of the main motor 70 and an actuator control unit 81 that controls driving of the motor 50 .

When releasing the locked state of the parking lock mechanism with the vehicle 100 tilted, the MG control unit 85 controls the main motor 70 so as to reduce the meshing load between the parking gear 35 and the parking lock pole 33 . Further, the actuator control unit 81 controls the motor 50 so that the locked state is released after the torque generation standby of the main motor 70 .

In this embodiment, when the parking lock is released with the vehicle 100 tilted, the torsional torque of the axle 95 is generated by the vehicle weight W received by the parking gear 35 from the wheels 98 and the load L corresponding to the tilt angle θ. Also, a meshing load is generated between the parking gear 35 and the parking lock pole 33, and this meshing load requires a larger torque to release the parking lock than on a flat road. In this embodiment, the torque of the motor 50 can be reduced by driving the main motor 70 when the P is removed in the vehicle tilting state.

Further, if the parking gear 35 and the parking lock pole 33 are disengaged in a state where the torsion of the axle 95 due to the weight of the vehicle is not completely canceled by the MG torque, there is a possibility that a shock may be generated due to the swing back due to the torsion component. be. In this embodiment, the driving of the motor 50 is controlled so that the locked state is released after the main machine motor 70 waits for torque generation. As a result, it is possible to reduce the shock caused by the swing back.

The motor 50 is a brushed DC motor, and the drive of the motor 50 is transmitted to the output shaft 15 via a power transmission section 510 composed of a spur gear. Further, when the main motor 70 is not driven when the vehicle 100 is steeply inclined, the locked state of the parking lock mechanism cannot be released by the torque of the motor 50 .

Even with a configuration such as a DC brushed motor and a spur gear, the load L due to the vehicle weight W is canceled by the main motor 70, so that the parking lock can be properly secured even when the vehicle is tilted. It is possible to cancel the state. In addition, assuming that the main motor 70 is driven when the parking lock is released when the vehicle is tilted, the motor 50 only needs to output the torque necessary for detent switching on a flat road, and the rotary actuator 40 is operated. It can be made smaller. Here, the "steeply inclined state" refers to a state in which the vehicle 100 is inclined to such an extent that the parking lock state cannot be released by the torque of the motor 50 while the cancellation torque of the main motor 70 is not being output. means.

(Second embodiment)
A second embodiment is shown in FIGS. 14-16. As described above, when the main motor 70 compensates for the torque shortage when the vehicle 100 is stopped on a slope, for example, the torsion of the axle 95 due to the load L may occur due to a delay in the torque rise of the main motor 70. If the parking lock pole 33 is disengaged from the parking gear 35 in a state in which the cancellation is not completed, there is a risk of a shock due to swinging back due to the torsion component.

Therefore, in the present embodiment, the detent is switched after the time corresponding to the rise of the torque of the main motor 70 has elapsed, thereby reducing the shock caused by the torsion of the axle when the P is pulled out. On the other hand, waiting for the torque of the main motor 70 to rise increases the time required for range switching. Therefore, energization is performed to the extent that it is possible to reduce the looseness during standby, thereby suppressing the decrease in responsiveness.

Here, as schematically shown in FIGS. 13 and 16 and the like, play including gear backlash is formed between the motor shaft 505 and the output shaft 15 . In FIG. 13 and the like, the power transmission portion 510 is collectively described as one gear. Here, the "play" can be understood as the total play and backlash that exists between the motor shaft 505 and the output shaft 15, and the total play is hereinafter simply referred to as the "play". Further, the state in which the power transmission unit 510 is pushed to one side of the backlash is defined as the "backlash reduction state", and the current to the extent that the backlash can be eliminated is defined as the backlash reduction current Ig.

In this embodiment, the MG control process is the same as in the above embodiment, so the description is omitted. The same applies to embodiments described later. Actuator control processing will be described based on the flowchart of FIG. S111 and S112 are the same as S501 and S502 in FIG. If the determination in S112 is negative, the process proceeds to S115, and if the determination is positive, the process proceeds to S113.

of the vehicle 100 is greater than the tilt determination threshold value .theta.th (S112: YES), the actuator control unit 81 sets the target value of the rotation angle sensor 68 to the tightness position. , a backlash reduction current Ig is applied to the motor 50 to reduce the backlash toward the notP range.

In S114, the actuator control unit 81 determines whether or not the waiting time Xwait after the notP switching request is input has exceeded the waiting determination time Xth. If it is determined that the standby time Xwait has not exceeded the standby determination time Xth (S114: NO), the process returns to S113 to continue the energization of the backlash elimination current Ig. If it is determined that the standby time Xwait has exceeded the standby determination time Xth (S114: YES), the process proceeds to S115, the target value of the rotation angle sensor 68 is set to the notP valley, and the switching current Ic capable of switching the detent mechanism is supplied. . The processes of S116 and S117 are the same as the processes of S103 and S104 in FIG.

The notP switching process of this embodiment will be described based on the time chart of FIG. At time x20, when the vehicle 100 is stopped on a slope where the inclination angle θ is greater than the inclination determination threshold value θth, and the notP switching request is input, the MG torque target value Ttgt is set, and the main motor 70 is driven.

In this embodiment, when the target value of the rotation angle sensor 68 is set to the backlash elimination position and the backlash elimination current Ig smaller than the switching current Ic is applied to the motor 50, the backlash is stopped at the time x21 when the backlash elimination position is reached ( See Figure 16).

At the time x22 when the standby determination time Xth has passed since the notP switching request was input, the target value of the rotation angle sensor 68 is set to the notP valley, and the energization of the motor 50 is changed from the backlash-removing current Ig to the switching current Ic. do. This drives the detent roller 26 to the notP valley. The processing after the detent roller 26 reaches the notP range is the same as in the above-described embodiment, so description thereof will be omitted. The same applies to other embodiments.

In the present embodiment, when the actuator control unit 81 acquires an unlock command for the parking lock mechanism 30 while the vehicle 100 is tilted, the actuator control unit 81 outputs a standby current that is smaller than the switching current Ic that is the unlock current required for unlocking. is supplied to the motor 50, and after the standby determination time Xth has elapsed, the current supplied to the motor 50 is switched to the switching current Ic, which is the unlocking current. In this embodiment, a play is formed between the motor shaft 505, which is the rotating shaft of the motor 50, and the output shaft 15 to which the driving force of the motor 50 is transmitted. This is the backlash elimination current Ig.

By energizing the switching current Ic after waiting for the torque of the main motor 70 to rise, it is possible to more reliably reduce the occurrence of shock caused by the twisting of the axle 95 due to the inclination of the vehicle 100 . In addition, by applying the backlash elimination current Ig during standby, the time for idle running of the motor shaft 505 in the play range is eliminated, so the time required for backlash elimination can be shortened. As compared with the case of not performing Also, during standby, by energizing the motor shaft 505 and the output shaft 15 so as to reduce the play between them, the detent roller 26 is positioned near the bottom of the P valley, so that the parking lock is released due to the occurrence of some kind of abnormality. Since the parking lock state is maintained even when canceling, safety can be ensured. Moreover, the same effects as those of the above-described embodiment can be obtained.

(Third embodiment)
A third embodiment will be described with reference to FIGS. 17 to 19. FIG. In the second embodiment, while waiting for the torque rise of the main motor 70, the backlash reduction current Ig is applied to reduce the backlash, thereby suppressing a decrease in responsiveness. In this embodiment, during standby, the output shaft 15 is driven within the P-lock holding range in which the parking lock pole 33 is not disengaged from the parking gear 35, thereby further reducing the decrease in responsiveness (see FIG. 19). ).

The actuator control processing of this embodiment will be described based on the flowchart of FIG. 17 . The processing of S121 and S122 is the same as the processing of S111 and S112 in FIG. In S123, the actuator control unit 81 sets the target value of the rotation angle sensor 68 to a predetermined position within the P lock holding range (hereinafter referred to as "P lock holding position"), and applies the lock holding current Ih1 to the motor 50. . The processing after S124 is the same as the processing after S114 in FIG.

The notP switching process of this embodiment will be described based on the time chart of FIG. At time x30, when the vehicle 100 is stopped on a slope where the inclination angle θ is greater than the inclination determination threshold value θth, and the notP switching request is input, the MG torque target value Ttgt is set, and the main motor 70 is driven.

In the present embodiment, when the target value of the rotation angle sensor 68 is the P lock holding position and the lock holding current Il is applied to the motor 50, the detent roller 26 stops at the P lock holding position at time x31 (Fig. 19). At this time, the state in which the parking lock pole 33 and the parking gear 35 are fitted together is continued. The processing after time x32 is the same as the processing after time x22 in FIG.

In this embodiment, the standby current is a lock holding current Ih1 which is in the unlocking direction and can be stopped at the lock holding position where the locked state of the parking lock mechanism can be held. As a result, it is possible to suppress a decrease in responsiveness compared to the case where no energization is performed during standby. Further, even if parking lock release is canceled due to the occurrence of some abnormality, the parking lock state is maintained, so safety can be ensured. Moreover, the same effects as those of the above-described embodiment can be obtained.

(Fourth embodiment)
A fourth embodiment will be described with reference to FIG. In this embodiment, the output shaft 15 is driven within the P-valley suction range in which the detent roller 26 can be dropped into the P-valley by the spring force of the detent spring 25, and waits within the P-valley suction range. If the standby position is within the P valley suction range, for example, even if range switching is to be stopped due to some abnormality, the detent roller 26 is moved by the spring force of the detent spring 25 by turning off the power supply to the motor 50 . can be reliably returned to the P valley.

The actuator control processing of this embodiment will be described based on the flowchart of FIG. The processing of S131 and S132 is the same as the processing of S111 and S112 in FIG. In S133, the actuator control unit 81 sets the target value of the rotation angle sensor 68 to a predetermined position within the P-valley suction range (hereinafter referred to as the "P-valley suction position"), and energizes the motor 50 with the suction position holding current Ih2. do. The processing after S134 is the same as the processing after S114 in FIG. In the time chart, the P lock holding position and the lock holding current Ih1 in FIG. 18 can be read as the P valley suction position and the suction position holding current Ih2, so description thereof will be omitted.

Since the P-valley suction range is determined by the configuration of the shift range switching mechanism 20 and the lock holding range is determined by the configuration of the parking lock mechanism 30, which one is wider depends on the design. Therefore, it is desirable that the holding position during standby is a position included in both the P-valley suction range and the lock holding range.

Motor 50 can drive parking lock pole 33 via shift range switching mechanism 20 . The shift range switching mechanism 20 includes a detent plate 21 that rotates together with the output shaft 15 and has a plurality of troughs 211 and 212 and ridges 215 that separate the troughs 211 and 212 . and a detent spring 25 that biases the detent roller 26 in a direction to fit into the troughs 211 and 212 .

The standby current in this embodiment is in the unlocking direction, and when the power to the motor 50 is turned off, the detent roller 26 is returned to the valley portion 211 corresponding to the P range by the biasing force of the detent spring 25. This is the suction position holding current Ih2 that can be stopped at the P suction position. As a result, even if range switching is canceled due to some kind of abnormality, the P range is maintained, so safety can be ensured. Moreover, the same effects as those of the above-described embodiment can be obtained.

(Fifth embodiment)
A fifth embodiment is shown in FIGS. The actuator control processing of this embodiment will be described based on the flowchart of FIG. The processing of S141-S143 is the same as the processing of S111-S113 in FIG.

At S144, the actuator control unit 81 determines whether or not the MG torque Tmg is greater than the torque determination threshold value Tth. The torque determination threshold value Tth is set according to the shortage of the torque that can be output by the motor 50 with respect to the torque required for P removal. The torque determination threshold value Tth may be a predetermined value, or may be variable according to the inclination angle θ or the like. If it is determined that the MG torque Tmg is equal to or less than the torque determination threshold value Tth (S144: NO), the process returns to S143 to continue application of the backlash elimination current Ig. When it is determined that the MG torque Tmg is greater than the torque determination threshold value Tth (S144: YES), the process proceeds to S145. The processing after S145 is the same as the processing after S115 in FIG.

The notP switching process of this embodiment will be described based on the time chart of FIG. The processing at time x40 and time x41 is the same as the processing at time x20 and time x21 in FIG. At time x42, when the MG torque Tmg reaches the torque determination threshold value Tth, the target value of the rotation angle sensor 68 is set to the notP valley, and the energization of the motor 50 is changed from the backlash-removing current Ig to the switching current Ic. This drives the detent roller 26 to the notP valley.

In this embodiment, as in the second embodiment, the backlash reduction current Ig is applied to wait at the backlash reduction position. It may be made to stand by at the holding position, or may be made to stand by at the P sucking position by energizing the sucking position holding current Ih2 as in the fourth embodiment.

When the actuator control unit 81 acquires an unlock command for the parking lock mechanism 30 while the vehicle 100 is tilted, the actuator control unit 81 applies a standby current smaller than the switching current Ic to the motor 50, and the output torque of the main motor 70 is increased. When it becomes larger than the torque determination threshold value Tth, the current supplied to the motor 50 is switched to the switching current Ic. As a result, the load L due to the tilt of the vehicle 100 can be reliably cancelled, and the P release operation can be performed. In addition, by applying the standby current during standby, it is possible to suppress the decrease in responsiveness as compared with the case where the electricity is not applied. Moreover, the same effects as those of the above-described embodiment can be obtained.

(Sixth embodiment)
A sixth embodiment is shown in FIG. The actuator control processing of this embodiment will be described based on the flowchart of FIG. The processing of S151 and S152 is the same as the processing of S111 and S112 in FIG. If the determination in S152 is negative, the process proceeds to S157, and if the determination is positive, the process proceeds to S153.

At S153, the actuator control unit 81 determines whether the TM oil temperature is low. Here, when the TM oil temperature is lower than the oil temperature determination threshold value, it is determined that the oil temperature is low. The oil temperature determination threshold is set according to the temperature at which response delay may occur due to friction or the like. If it is determined that the TM oil temperature is not low (S153: NO), the process proceeds to S156, and if it is determined that the TM oil temperature is low (S153: YES), the process proceeds to S154.

At S154, the actuator control section 81 energizes the motor 50 with the suction position holding current Ih2, as at S133 in FIG. A backlash elimination current Ig or a lock holding current Ih1 may be used instead of the suction position holding current Ih2.

In S155, as in S114 and the like, the actuator control section 81 determines whether or not the waiting time Xwait exceeds the waiting determination time Xth. If it is determined that the standby time Xwait is equal to or shorter than the standby determination time Xth (S155: NO), the process returns to S154 to continue energization of the suction position holding current Ih2. If it is determined that the waiting time Xwait has exceeded the waiting determination time Xth (S155: YES), the process proceeds to S157.

In S156 to which the process proceeds when the TM oil temperature is not low (S153: NO), as in S155, the actuator control unit 81 determines whether or not the waiting time Xwait exceeds the waiting determination time Xth. If it is determined that the standby time Xwait is equal to or shorter than the standby determination time Xth (S156: NO), this determination process is repeated. If it is determined that the waiting time Xwait has exceeded the waiting determination time Xth (S156: YES), the process proceeds to S157. The processing after S157 is the same as the processing after S115 in FIG. Incidentally, instead of the determinations of S155 and S156, a determination based on the MG torque may be made as in S144 in FIG.

That is, in the present embodiment, when the TM oil temperature is low and there is concern about a decrease in response, the decrease in response is suppressed by energizing during standby. On the other hand, if the TM oil temperature is not low and the responsiveness does not matter so much, power is not supplied during standby. In other words, if there is a demand for responsiveness, energization during standby is performed, and if there is no demand for responsiveness, energization during standby is canceled. Thereby, power consumption can be reduced.

In the present embodiment, the actuator control section 81 energizes the standby current when the oil temperature of the transmission 7 connected to the shift range switching mechanism 20 is lower than the oil temperature determination threshold. In other words, when the oil temperature of the transmission 7 is equal to or higher than the oil temperature determination threshold value, no current is applied during standby. Power consumption can be reduced by limiting the application of standby current to low oil temperatures where there is a concern that responsiveness will be lowered. Moreover, the same effects as those of the above-described embodiment can be obtained.

(Seventh embodiment)
A seventh embodiment is shown in FIG. If a constant current continues to flow during standby, there is a risk that uneven heat generation will occur among the switching elements that make up the drive circuit. Therefore, in the present embodiment, as shown in FIG. 24, during standby, a minute current oscillation is applied so that the average current becomes the loose current Ig. By oscillating the current, the difference in on-time between the switching elements becomes smaller than in the case of applying a constant current, and uneven heat generation can be reduced. The amplitude of the current is set according to the configuration of the shift range switching mechanism 20 and the like so that the looseness is not released. It should be noted that although the average current during standby has been described as being the backlash reduction current Ig, it may instead be the lock holding current Ih1 or the suction position holding current Ih2.

The actuator control unit 81 applies current vibration to the standby current. As a result, it is possible to reduce energization between the switching elements and uneven heat generation due to the energization during the energization of the standby current. Moreover, the same effects as those of the above-described embodiment can be obtained.

(Eighth embodiment)
An eighth embodiment is shown in FIG. The parking lock mechanism 30 of this embodiment is driven by a direct acting actuator 75 . Direct-acting actuator 75 directly drives parking rod 31 without going through shift range switching mechanism 20 . In addition, it is preferable that the direct-acting actuator 75 is provided with a self-locking mechanism so that the parking lock is not released by an external force or the like. The notP switching control may be any control of the above embodiments.

In the embodiment, the vehicle drive system 90 is the "parking lock system", the motor 50 and the direct acting actuator 75 are the "actuators", the shift range switching mechanism 20 is the "detent mechanism", the detent plate 21 is the "driven member", the detent The spring 25 corresponds to the "biasing member", the detent roller 26 to the "engagement member", the parking lock pole 33 to the "parking lever", and the MG control section 85 to the "main motor control section". Further, the switching current Ic corresponds to the "unlock current", the backlash reduction current Ig, the lock holding current Ih1 and the suction position holding current Ih2 correspond to the "standby current".

(Other embodiments)

In the above embodiment, the number of speed reduction stages is three. In other embodiments, the number of reduction stages may be two, four or more. Further, it is sufficient that the drive of the motor can be transmitted to the output shaft, and the configuration of the mechanism for transmitting power from the motor to the output shaft may be different.

In the above embodiments, the motor is a brushed DC motor. In other embodiments, the motor may be other than a brushed DC motor. Further, in the above-described embodiment, when the main motor is not driven in a steeply inclined state, the parking lock cannot be released by the torque of the actuator. In another embodiment, an actuator that can unlock without driving the main motor when the vehicle is steeply tilted may be used. Even in such a case, the load on the actuator can be reduced by outputting at least part of the canceling torque from the main motor.

In the above embodiment, the detent plate is provided with two valleys. In other embodiments, the number of valleys is not limited to two, and may be three or more. Also, the shift range switching mechanism, the parking lock mechanism, and the like may be different from those in the above embodiment.

The controller and techniques described in this disclosure may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by the computer program. may be Alternatively, the controls and techniques described in this disclosure may be implemented by a dedicated computer provided by configuring the processor with one or more dedicated hardware logic circuits. Alternatively, the control units and techniques described in this disclosure can be implemented by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. It may also be implemented by one or more dedicated computers configured. The computer program may also be stored as computer-executable instructions on a computer-readable non-transitional tangible recording medium. As described above, the present invention is by no means limited to the above embodiments, and can be embodied in various forms without departing from the gist of the invention.

20: Shift range switching mechanism (detent mechanism)
30 Parking lock mechanism 33 Parking lock pole (parking lever)
35 Parking gear 50 Motor (actuator) 70 Main motor 60 Linear actuator (actuator)
80... Control unit 81... Actuator control unit 85... MG control unit (main motor control unit)
90... Vehicle drive system (parking lock system)
95 Axle 100 Vehicle

Claims (9)

a main motor (70) as a driving source of the vehicle (100);
A parking lock mechanism having a parking lever (33) meshable with a parking gear (35) connected to an axle (95), and locking the rotation of the axle by meshing the parking gear and the parking lever. (30) and
an actuator (50, 75) capable of driving the parking lever;
a control unit (80) having a main motor control unit (85) that controls the main motor and an actuator control unit (81) that controls the actuator;
with
When releasing the locked state of the parking lock mechanism while the vehicle is tilted,
The main motor control unit controls the main motor so as to reduce a meshing load between the parking gear and the parking lever,
The parking lock system, wherein the actuator control unit controls the actuator so that the locked state is released after waiting for torque generation by the main motor. When the actuator control unit receives an unlocking command for the parking lock mechanism while the vehicle is tilted, the actuator control unit applies a standby current smaller than an unlocking current required for unlocking to the actuator, and waits for a standby determination time. 2. The parking lock system according to claim 1, wherein the current applied to said actuator is switched to said unlocking current after a lapse of time. When the actuator control unit receives an unlock command for the parking lock mechanism while the vehicle is tilted, the actuator control unit energizes the actuator with a standby current that is smaller than an unlock current required for unlocking the main motor. 2. The parking lock system according to claim 1, wherein the current applied to the actuator is switched to the unlocking current when the output torque of the parking lock exceeds a determination threshold value. A play is formed between the rotary shaft (505) of the actuator and the output shaft (15) to which the drive of the actuator is transmitted,
4. The parking lock system according to claim 2 or 3, wherein said standby current is a backlash reduction current for reducing said play on the unlocking side. 4. The parking lock system according to claim 2, wherein the standby current is a lock holding current that can be stopped at a lock holding position where the locked state of the parking lock mechanism can be held. The actuator is capable of driving the parking lever via a detent mechanism (20),
The detent mechanism includes a driven member (21) formed with a plurality of troughs (211, 212) and peaks (215) separating the troughs, rotating together with the output shaft (15), and rotating the driven member (21). an engaging member (26) movable between the valleys, and a biasing member (25) biasing the engaging member in a direction to fit into the valleys;
The current during standby is at the P valley suction position where the engaging member is returned to the valley portion (211) corresponding to the P range by the biasing force of the biasing member when the power supply to the actuator is turned off. 4. A parking lock system according to claim 2 or 3, which is a stoppable suction position holding current. The actuator is capable of driving the parking lever via a detent mechanism (20),
7. The actuator control unit according to any one of claims 2 to 6, wherein when the oil temperature of the transmission (7) connected to the detent mechanism is lower than the oil temperature determination threshold value, the current during standby is supplied. parking lock system. The parking lock system according to any one of claims 2 to 7, wherein the actuator control section applies current vibration to the standby current. The actuator is a brushed DC motor,
The parking lock system according to any one of claims 1 to 8, wherein the drive of the actuator is transmitted to the output shaft (15) by a power transmission section (510) composed of a spur gear.

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