JP2013253632A - Speed-change control method for electric vehicle, and speed-change control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speed-change control method for an electric vehicle and a speed-change control apparatus, by which erroneous determination on canceling the engagement of a roller clutch in a current speed-change stage is prevented and reduction of a speed-change time, and the like can be achieved.SOLUTION: A speed-change control method includes a clutch cancellation step S2, a synchronization step S3, and clutch engagement steps S4, S5. The synchronization step S3 carried out after the clutch cancellation step S2 includes: a first cancellation determination step of determining, after a given time has passed from starting an electric motor synchronization operation, whether or not the engagement of a roller clutch for a current speed-change stage is canceled; and a second cancellation determination step of determining, if it is determined by the first cancellation determination step that the engagement of the roller clutch for at least the current speed-change stage is not canceled, whether or not the engagement of the roller clutch for the current speed-change stage is canceled after a further given time has passed.

Description

  The present invention relates to a shift control method and a shift control apparatus for an electric vehicle that shifts the rotation of an electric motor and transmits the rotation to a wheel, and relates to a technique for determining release of a roller clutch engagement at a current shift stage.

  As a drive device for an electric vehicle, there is a vehicle motor drive device that transmits power to drive wheels via an electric motor, a transmission, and a differential (differential). For example, a two-way roller clutch is used for switching the gear position of the transmission.

  When this vehicle motor drive device is used, it is possible to use the electric motor in a highly efficient rotational speed and torque region during driving and regeneration by switching the transmission gear ratio according to the running conditions. . In addition, by setting an appropriate gear ratio, the rotational speed of the rotating member of the transmission during high-speed traveling can be reduced, and the power loss of the transmission can be reduced to improve the energy efficiency of the vehicle. As such a vehicle motor drive device, for example, those described in Patent Literature 1 and Patent Literature 2 are known.

JP 2011-57030 A JP-A-8-168110

  In the vehicle motor drive device described in Patent Document 1 or the like, there is a problem that a large shift shock torque and abnormal noise are generated when a roller clutch is engaged at a target shift stage of the transmission when the shift is switched. In particular, if there is a large rotational speed difference between the rotational speed of the second shaft of the transmission and the rotational speed of the outer ring when the contact between the friction plate of the target gear stage and the outer ring is completed, a large shift shock torque and abnormal noise are generated. Therefore, a shift control method for reducing shift shock torque has been proposed.

  As such a shift control method, the target rotational speed of the electric motor is calculated based on the vehicle speed at the time of shift switching and the speed ratio of the selected target shift stage, and the output of the electric motor is output according to the target rotational speed of the electric motor. Has been proposed (for example, Japanese Patent Application No. 2011-123433). This proposed example is a control method for switching between two feedback controls of torque control and rotation speed control. In this proposed example, the rotational speed of the electric motor may fluctuate when the engagement (engagement) of the roller clutch at the current gear stage is released during gear shifting. Due to the fluctuation of the rotation speed of the electric motor, there is a possibility that a determination error that the engagement of the roller clutch at the current shift stage is not released but the release is not made may occur. Performing the synchro operation again due to this determination error leads to problems such as an increase in shifting time and energy consumption.

  An object of the present invention is to provide a shift control method and a shift control device for an electric vehicle that can prevent a misjudgment of disengagement of a roller clutch at a current shift stage and can reduce a shift time.

The speed change control method for an electric vehicle according to the present invention includes a plurality of gear stages LA and LB having different speed ratios, and an input shaft 7 connected to a motor shaft 4 that is an output shaft of the electric motor 3 for traveling. The two-way roller clutches 16A and 16B of each gear stage that are interposed between the gear trains LA and LB of the respective gear stages and can be switched intermittently, and the intermittent switching of these roller clutches 16A and 16B. A transmission 5 having a transmission ratio switching mechanism 40 for performing,
Each of the roller clutches 16A and 16B has a roller 20 interposed in each wedge-shaped space S provided between the cam surfaces 19 of the inner rings 18A and 18B and the outer rings 23 and 23, and each roller 20 is engaged with a narrow portion of the wedge-shaped space S. It is a configuration in which it is in a connected state by being combined, and it is in a disconnected state by positioning each roller 20 in the expanded portion of the wedge-shaped space S by the cages 21A and 21B.
The gear ratio switching mechanism 40 is a mechanism that switches the contact and separation of the friction plates 35A and 35B connected to the retainers 21A and 21B to and from the outer rings 23 and 23 by the shift switching actuator 47 moving forward and backward. is there,
In a shift control method for an electric vehicle,
In response to a shift command to the target shift stage, the shift switching actuator 47 operates the shift member 45 to unload the torque of the electric motor 3 and engage the roller clutches 16A and 16B at the current shift stage. The clutch release process to release,
A synchronization process in which the rotation speed of the outer clutches 23 and 23 of the roller clutches 16A and 16B and the rotation speeds of the inner rings 18A and 18B of the target gear stage are synchronized by controlling the rotation speed of the electric motor 3;
A clutch engagement process for engaging the target gear stage roller clutches 16A and 16B by bringing the friction plates 35A and 35B of the target gear stage into contact with the outer rings 23 and 23 and controlling the rotational speed of the electric motor 3; ,
Have
After the clutch release process, the sync process includes:
A first release determination process for determining whether or not the engagement of the roller clutches 16A and 16B at the current gear stage has been released after a lapse of a certain time since the start of a synchronization operation for increasing or decreasing the rotation speed of the electric motor 3. When,
In this first release determination process, if it is determined that at least the engagement of the roller clutches 16A and 16B at the current gear stage has not been released, the roller clutches 16A and 16B at the current gear stage are further passed after a predetermined time has passed. A second release determination process for determining whether or not the engagement is released;
It is characterized by having.

  According to this method, in the clutch release process, the shift member 45 is operated by the shift switching actuator 47 in response to a shift command to the target shift stage. As a result, the torque of the electric motor 3 is unloaded and the engagement of the roller clutches 16A and 16B at the current gear stage is released. In the synchronization process, the electric motor 3 is synchronized so that the rotational speeds of the outer wheels 23, 23 of the roller clutches 16A, 16B and the inner rings 18A, 18B of the target gear stage are synchronized by controlling the rotational speed. Thereafter, in the clutch engagement process, the friction plates 35A and 35B at the target gear stage and the outer wheels 23 and 23 are brought into contact with each other, and the electric motor 3 is controlled in rotational speed, thereby engaging the roller clutches 16A and 16B at the target gear stage. Let

  In the first release determination process in the synchronization process after the clutch release process, the engagement of the roller clutches 16A and 16B at the current gear stage is released after a certain period of time has elapsed since the start of the synchronization operation of the electric motor 3 by the rotational speed control. A first determination is made as to whether or not the operation has been performed. If it is determined in this first release determination process that at least the engagement of the current shift speed is not released, after a certain period of time has elapsed, in the second release determination process, the roller clutch 16A, A second determination is made as to whether the engagement of 16B has been released. Therefore, if it is determined in the first release determination process that the engagement of the current shift stage is once released, then, for example, even if the rotational speed of the electric motor 3 fluctuates, It is possible to reliably prevent erroneous determination that the match is not released. As a result, it is possible to prevent the synchronization operation from being performed again, shorten the speed change time, and prevent energy consumption.

In the first release determination process, when it is determined that the engagement of the roller clutches 16A and 16B at the current shift stage is released, the determination of disengagement in the second release determination process may not be performed. good. In this case, the determination in the second release determination process can be omitted, and the shift time can be reliably shortened.
When it is determined in the first release determination process that the engagement of the roller clutches 16A and 16B at the current gear stage has not been released, a determination of disengagement in the second release determination process is performed. Also good.

In the first release determination process, when it is determined that the engagement of the roller clutches 16A and 16B at the current shift stage is not released, before performing the engagement release determination in the second release determination process, A synchronization operation completion determination process for determining whether or not the synchronization operation of the electric motor 3 has been completed. In this synchronization operation completion determination process, a determination is made that the synchronization operation has not been completed. The determination of disengagement in the process may be performed, and the determination of disengagement in the second disengagement determination process may not be performed based on the determination that the synchronization operation has been completed.
Thus, after the first release determination process, before the second release determination process, the synchronization operation completion determination process is determined. When the synchronization operation is completed, the synchronization process can be preferentially terminated, and the next clutch engagement process can be shifted without delay.

  In the synchronization process, the synchronization operation of the electric motor 3 may be continued regardless of the determination result of the first release determination process. In this case, the electric motor 3 can be smoothly synchronized, and the change rate of the rotation speed in the electric motor 3 can be reduced. As a result, it is possible to make it difficult for abnormal noise caused by backlash between the gears.

Only when the rotational speed of the electric motor 3 becomes larger than the rotational speed obtained by multiplying the output rotational speed by the speed reduction ratio of the current shift speed plus a constant rotational speed at the time of downshifting. It may be determined that the engagement of the stage roller clutches 16A and 16B has been released.
Only when the rotational speed of the electric motor 3 becomes smaller than the rotational speed obtained by multiplying the output rotational speed by the speed reduction ratio of the current shift stage and a predetermined rotational speed at the time of shift-up. It may be determined that the engagement of the stage roller clutches 16A and 16B has been released.

  The determination as to whether or not the engagement of the roller clutches 16A and 16B at the current gear stage has been released may be performed only when the shift lever is selected in the drive range.

The shift control apparatus for an electric vehicle according to the present invention includes a gear train of a plurality of shift stages having different gear ratios, an input shaft connected to a motor shaft that is an output shaft of a traveling electric motor, and a gear of each of the shift stages. A transmission having a two-way roller clutch of each gear stage that is interposed between each row and can be switched intermittently, and a gear ratio switching mechanism that switches between the intermittent states of each of the roller clutches,
Each roller clutch is in a connected state when a roller is interposed in each wedge-shaped space provided between the cam surface of the inner ring and the outer ring, and each roller engages with a narrowed portion of the wedge-shaped space. It is configured to be in a cut state by being positioned in the spread part of the wedge-shaped space,
The transmission ratio switching mechanism is a mechanism that switches contact and separation of a rotating friction plate connected to a retainer with an outer ring by advancing and retreating a shift member by a transmission switching actuator.
A shift control device for an electric vehicle,
In response to a shift command to a target shift stage, the shift member is operated by the shift switching actuator to unload the torque of the electric motor and release the engagement of the roller clutch of the current shift stage. Release means,
Synchronization control means for synchronizing the rotation speed of the outer ring and the inner ring of the roller clutch at the target gear stage by synchronizing the rotation speed of the electric motor;
Target gear stage clutch engagement means for engaging a roller clutch of the target gear stage by bringing the friction plate of the target gear stage into contact with the outer ring and controlling the rotational speed of the electric motor;
Have
The synchronization control means includes
A first release determination means for determining whether or not the engagement of the roller clutch at the current gear stage has been released after a lapse of a certain time since the start of the synchronization operation for increasing or decreasing the rotation speed of the electric motor;
When it is determined by the first release determination means that at least the engagement of the roller clutch at the current shift stage has not been released, the engagement of the roller clutch at the current shift stage is released after a predetermined time has passed. Second release determination means for determining whether or not
It is characterized by having.

  According to this configuration, if it is determined by the first release determination means that the engagement of the current shift stage is once released, then, for example, even if the rotational speed of the electric motor fluctuates, the current shift stage is changed. It is possible to reliably prevent erroneous determination that the engagement is not released. As a result, it is possible to prevent the synchronization operation from being performed again, shorten the speed change time, and prevent energy consumption.

The shift control method for an electric vehicle according to the present invention includes a gear train of a plurality of shift stages having different gear ratios, an input shaft connected to a motor shaft that is an output shaft of a traveling electric motor, and a gear of each of the shift stages. A transmission having a two-way roller clutch of each gear stage that is interposed between each row and capable of switching between on and off, and a gear ratio switching mechanism that switches between on and off of each of the roller clutches, The roller clutch is in a connected state when a roller is interposed in each wedge-shaped space provided between the cam surface of the inner ring and the outer ring, and each roller engages with a narrow portion of the wedge-shaped space. The gear ratio switching mechanism is configured to shift the contact and separation of the rotating friction plate connected to the retainer to the outer ring with a shift switching actuator. A mechanism for switching by the advance and retreat, in the shift control method in an electric vehicle,
A clutch release process in which the shift member is operated by the shift switching actuator in response to a shift command to the target shift stage, the torque of the electric motor is unloaded, and the roller clutch of the current shift stage is released; A synchronization process for synchronizing the rotation speed of the outer ring and the inner ring of the roller clutch at the target shift stage by controlling the rotation speed of the electric motor, and bringing the friction plate and the outer ring of the target shift stage into contact with each other. A clutch engagement process for engaging the roller clutch of the target shift stage by controlling the rotation speed of the electric motor,
After the clutch release process, the sync process starts whether or not the engagement of the roller clutch at the current gear stage has been released after a lapse of a certain time after starting the sync operation for increasing or decreasing the rotation speed of the electric motor. In the first release determination process to be determined and in the first release determination process, when it is determined that at least the engagement of the roller clutch at the current shift stage is not released, the current shift is further performed after a predetermined time has elapsed. A second release determination process for determining whether or not the engagement of the stage roller clutch has been released. Therefore, it is possible to prevent misjudgment of disengagement of the roller clutch at the current shift stage, and to reduce the shift time.

The shift control apparatus for an electric vehicle according to the present invention includes a gear train of a plurality of shift stages having different gear ratios, an input shaft connected to a motor shaft that is an output shaft of a traveling electric motor, and a gear of each of the shift stages. A transmission having a two-way roller clutch of each gear stage that is interposed between each row and capable of switching between on and off, and a gear ratio switching mechanism that switches between on and off of each of the roller clutches, The roller clutch is in a connected state when a roller is interposed in each wedge-shaped space provided between the cam surface of the inner ring and the outer ring, and each roller engages with a narrow portion of the wedge-shaped space. The gear ratio switching mechanism is configured to shift the contact and separation of the rotating friction plate connected to the retainer to the outer ring with a shift switching actuator. A mechanism for switching by the advance and retreat, a shift control device in an electric vehicle,
In response to a shift command to a target shift stage, the shift member is operated by the shift switching actuator to unload the torque of the electric motor and release the engagement of the roller clutch of the current shift stage. Release means, synchronization control means for synchronizing the rotation speed of the outer ring and the inner ring of the roller clutch at the target shift stage by controlling the rotation speed of the electric motor, and the friction plate and the outer ring of the target shift stage And a target gear stage clutch engaging means for engaging the roller clutch of the target gear stage by controlling the number of rotations of the electric motor.
The synchronization control means starts a synchronization operation for increasing or decreasing the rotational speed of the electric motor and, after a predetermined time has elapsed, determines whether or not the engagement of the roller clutch at the current gear stage has been released. If it is determined by the determination means and the first release determination means that at least the engagement of the roller clutch at the current shift stage has not been released, the engagement of the roller clutch at the current shift stage after a certain time has passed. And a second release determination means for determining whether or not the connection has been released. Therefore, it is possible to prevent misjudgment of disengagement of the roller clutch at the current shift stage, and to reduce the shift time.

1 is a schematic diagram of an electric vehicle to which a shift control method and a shift control apparatus according to an embodiment of the present invention are applied. It is the schematic of the hybrid vehicle to which the same shift control method and shift control device are applied. It is sectional drawing of the motor drive device for vehicles of the vehicle shown in FIG. 1, FIG. It is sectional drawing of the reduction ratio switching mechanism of the motor drive device for vehicles. It is a schematic block diagram of the transmission control system which controls the motor drive device for vehicles. It is a block diagram of the inverter apparatus of the motor drive apparatus for vehicles. It is explanatory drawing of the lever operation panel of the vehicle. It is a block diagram of the inverter control apparatus of the motor drive device for vehicles. It is a block diagram which shows the conceptual structure of the transmission control apparatus of the motor drive device for vehicles. It is an automatic shift diagram in the same shift control method. It is a block diagram of the upshift automatic shift line map in the shift control method. It is a block diagram of the downshift automatic shift line map in the shift control method. 3 is a flowchart of automatic shift determination in the shift control method. It is a flowchart which shows the outline | summary of the speed-change control method. 7 is a flowchart for determining release of a current gear clutch at the time of downshifting in the same shift control method. 7 is a flowchart for determining release of a current shift stage clutch at the time of upshifting in the same shift control method. FIG. 5 is a partial enlarged cross-sectional view of FIG. 4. FIG. 5 is a sectional view taken along line XVIII-XVIII in FIG. 4. It is sectional drawing along the XIX-XIX line | wire of FIG. It is sectional drawing along the XX-XX line of FIG. It is sectional drawing which shows the shift mechanism of the motor drive device for vehicles. FIG. 5 is an exploded perspective view of a roller clutch and the like in the reduction ratio switching mechanism of FIG. 4.

  Hereinafter, a shift control method for an electric vehicle according to an embodiment of the present invention will be described. The following description also includes a description of the shift control device. FIG. 1 shows an electric vehicle EV in which a pair of left and right front wheels 1 are drive wheels driven by a vehicle motor drive device A, and a pair of left and right rear wheels 2 are driven wheels.

  FIG. 2 shows a hybrid vehicle HV in which a pair of left and right front wheels 1 are main drive wheels driven by an engine E, and a pair of left and right rear wheels 2 are auxiliary drive wheels driven by a vehicle motor drive device A. The hybrid vehicle HV is provided with a transmission T for shifting the rotation of the engine E and a differential D for distributing the rotation output from the transmission T to the left and right front wheels 1. The speed change control method and speed change control device of this embodiment are applied to the vehicle motor drive device A shown in FIGS.

  As shown in FIG. 3, the vehicle motor drive device A includes a traveling electric motor 3, a transmission 5 that shifts and outputs the rotation of the output shaft 4 of the electric motor 3, and an output from the transmission 5. The differential 6 is distributed to the pair of left and right front wheels 1 of the electric vehicle EV shown in FIG. 1 or to the pair of left and right rear wheels 2 of the hybrid vehicle shown in FIG.

  The transmission 5 has two gear stages, and as shown in FIG. 3, a plurality of gear trains LA and LB (two trains in this example) having different gear ratios, and the output of the electric motor 3. Two-way type roller clutches 16A and 16B for each gear stage, which are respectively connected to the gear shaft LA and LB of each gear stage and can be switched intermittently. And a gear ratio switching mechanism 40 for switching the on / off state of the roller clutches 16A and 16B.

  The transmission 5 and the gear ratio switching mechanism 40 will be briefly described here within a range necessary for understanding the shift control method / device, and will be described in detail after the description of the shift control method / device.

  The transmission 5 includes an input shaft 7 to which the rotation of the motor shaft 4 is input, an output shaft 8 disposed in parallel to the input shaft 7 at a distance from each other, and a parallel having the gear trains LA and LB. It is a shaft always meshing transmission. The input gear 9A of the first gear train LA and the input gear 9B of the second gear train LB are integrally provided on the input shaft, and the output gear 10A of the first gear train LA and the output gear 10B of the second gear train LB are output shafts. 8 is rotatably installed on the outer periphery. The roller clutches 16A and 16B are interposed between the output gears 10A and 10B and the output shaft 8.

  The roller clutches 16A and 16B are each formed of a flat cam surface 19 and an outer ring 23 on the outer periphery of an inner ring 18B having a polygonal outer peripheral surface, as described in the example of the two-speed roller clutch 16B shown in FIG. A roller 20 is interposed in each wedge-shaped space S provided between the inner circumferential cylindrical surfaces. In the wedge-shaped space S, both sides in the circumferential direction are narrowed, and the center in the circumferential direction is an expanded portion. The roller clutches 16A and 16B are connected when the rollers 20 are engaged with the narrowed portions of the wedge-shaped space S, and are disconnected when the rollers 20 are positioned at the expanded portions of the wedge-shaped space S by the cage 21B. It is the composition which becomes.

  As shown in FIG. 4, the gear ratio switching mechanism 40 switches between contact and separation of the annular friction plates 35A and 35B, which are connected to the cages 21A and 21B of the roller clutches 16A and 16B and rotate, with the outer ring 23. This is a mechanism that is switched by the advancement and retraction of the shift fork 45 that is a shift member by the actuator 47. The shift mechanism 41 is a mechanism part that operates the friction plates 35 </ b> A and 35 </ b> B in the speed ratio switching mechanism 40, and includes a speed change switching actuator 47 and a shift fork 45.

  The shift switching actuator 47 is an electric motor for shifting. The rotation of the output shaft 47a is converted into a linear motion of the shift rod 46 by the feed screw mechanism 48, and the shift fork 45 attached to the shift rod 46 is axially moved. Move to. As the shift fork 45 moves, the shift sleeve 43 and the shift ring 34 move. Shift ring 34 presses friction plates 35A and 35B against the side surface of clutch outer ring 23 (output gears 10A and 10B). As a result, when the inner rings 18A, 18B with cam surfaces and the outer ring 23 rotate relative to each other, a frictional force (torque) acts between the friction plates 35A, 35B and the outer ring 23 via the cages 21A, 21B. Thus, the roller 20 can be pushed into the narrowed portion of the wedge-shaped space S.

  The cages 21A and 21B are rotatable with respect to the inner rings 18A and 18B. However, the switch springs 22A and 22B (FIG. 17) allow the center of the cam surface 19 (FIG. 17) of the inner rings 18A and 18B. The neutral position where S is spread and the center of the pocket 21a in the circumferential direction are biased. The friction plates 35A and 35B are connected to the switch springs 22A and 22B so as to be rotatable together with the cages 21A and 21B.

  FIG. 5 is a block diagram showing a control system for controlling the vehicle motor drive device A. As shown in FIG. This control system has an integrated ECU 60, a transmission ECU 61, and an inverter device 62. Signal transfer among the three units of the integrated ECU 60, the shift ECU 61, and the inverter device 62 is performed by CAN communication (controller area network).

  The integrated ECU 60 is an electronic control device that performs cooperative control among all on-vehicle electronic control devices, and includes an accelerator opening sensor 63a of the accelerator pedal 63, a brake opening sensor 91a of the brake pedal 91, and a steering angle sensor 92a of the steering wheel 92. The shift lever 93 is connected to a lever position sensor 93a for manually switching the gear position. The integrated ECU 60 shifts the accelerator position sensor 63a, the brake position sensor 91a, the steering angle sensor 92a, the accelerator position signal detected by the lever position sensor 93a, the brake position signal, the steering angle signal, and the lever position signal. A function to transmit to the ECU 61 and a function to perform the cooperative control by these four types of signals and signals from various other sensors and the like are provided.

  The shift ECU 61 is an electronic control device that controls automatic shift based on various signals transmitted from the ECU 60 and various signals directly input to the shift ECU 61. The shift ECU 61 performs shift determination based on the various input signals. 5 and a command to the inverter device 62.

The transmission ECU 61 includes the following functions (1) to (8).
(1) The vehicle speed sensor 94 and the acceleration sensor 95 receive vehicle speed and vehicle acceleration / deceleration detection signals, the accelerator opening signal is received from the integrated ECU 60, and automatic shift determination is performed.
(2) If it is determined that the brake is sudden, automatic shift is not performed.
(3) If it is determined that the steering wheel is a sudden handle, automatic shifting is not performed.
(4) The position signal of the shift lever 93 is received from the integrated ECU 60 and the creep control of the electric motor 3 is performed.

(5) Control according to operation of the 1st-3rd operation switch 96-98 operated by the driver | operator is performed.
First operation switch 96: an automatic / manual shift switching toggle switch.
Second operation switch 97: This is a tact switch, and is effective only when the first operation switch 96 is set by manual shifting. When the second operation switch 97 is pressed, an upshift is performed.
Third operation switch 98: a tact switch, which is valid only when the first operation switch 96 is set by manual shifting. When the third operation switch 98 is pressed, a downshift is performed.

(6) The vehicle speed, electric motor rotation speed, torque command value, etc. are displayed on the display unit 99. The display unit 99 is a device that displays an image, such as a liquid crystal display device, or a device that displays a pointer.
(7) A function of detecting the shift position of the shift switching actuator 47 from a shift position sensor 68 attached to the transmission 5 and a function of acquiring the rotation speed of the electric motor 3 from the inverter are provided.
(8) A function of transmitting a torque command or a rotational speed command and a shift command to the inverter device 62 and a function of driving a shift switching actuator 47 attached to the transmission 5 are provided.

The shift ECU 61 is programmed with shift modes of an automatic shift mode and a manual shift mode, and the automatic shift mode and the manual shift mode are switched by the operation of the first operation switch 96 by the driver.
The speed change control method and speed change control device of this embodiment relate to control in the automatic speed change mode by the speed change ECU 61. The transmission ECU 61 has various function achievement means (81 to 86) shown in FIG. 9, which will be described later.

  In FIG. 5, the inverter device 62 is supplied with DC power from the battery 69, supplies AC motor driving power to the electric motor 3, and controls the supplied power based on a signal from the transmission ECU 61. A signal indicating the number of rotations of the electric motor 3 is input to the inverter device 62 from a rotation angle sensor 66 that is a rotation detection device provided in the electric motor 3.

  The inverter device 62 has a function of driving the electric motor 3 and a function of obtaining a rotation angle signal of the electric motor 3 from the rotation angle sensor 66. As shown in FIG. 6, the inverter device 62 includes an inverter 71 and an inverter control circuit 72 that controls the inverter 71. Each phase of the electric motor 3 (at the connection point of the inverter 71, U, V, W phase upper arm switching elements Up, Vp, Wp and U, V, W phase lower arm switching elements Un, Vn, Wn) U, V, W phase) terminals are connected. To the inverter 71, an open / close command is given to each switching element Up, Vp, Wp, Un, Vn, Wn from the inverter control circuit 72 so as to output three-phase AC power.

  The electric motor 3 performs commutation by energization of three phases. In response to the demand for high torque, a large current is required for driving the electric motor 3.

  FIG. 7 shows the configuration of the shift lever operation panel 75. As the driver manually operates the shift lever 93 (FIG. 5), P (parking), R (reverse), N (neutral), D (drive), 2nd speed (second), Each range of 1st speed (low) can be switched. The shift lever operation panel 75 is a display device indicating which range is currently switched in this way. Range selection information on the shift lever operation panel 75 is input to the integrated ECU 60. The first speed range is the first speed state. The shift lever operation panel 75 may serve as a touch panel type input means and may be an operation means operated by a driver instead of the shift lever 93.

  FIG. 8 shows a block diagram of the electric motor 3, inverter torque control, and inverter rotation speed control. The inverter control circuit 72 can be controlled by switching between torque control and rotation speed control. Both torque control and rotation speed control are feedback control and vector control. Torque control and rotation speed control are performed at the time of shifting, and torque control is performed at times other than shifting. Detailed description is omitted here.

  The power converter 62a performs PWM control of the inverter 71 according to the PWM duties Vu, Vv, and Vw, and drives the electric motor 3.

The rotation speed control by the inverter control circuit 72 of FIG.
The speed command unit 106 is a means for giving a speed command to the inverter control circuit 72 and is provided in the speed change ECU 61. The speed command unit 106 calculates a target rotational speed of the electric motor 3 based on the vehicle speed at the time of shifting and the speed ratio of the selected target shift stage. The calculated target rotational speed is instructed to the inverter control circuit 72 of the inverter device 62 as a speed command.

Further, the rotor angle of the electric motor 3 is acquired from the rotation angle sensor 66, and the actual rotation speed of the electric motor 3 is calculated by the speed calculation unit 108. The comparison unit 109 obtains the difference between the speed command of the speed command unit 106 and the actual electric motor rotation number calculated by the speed calculation unit 108, and the control unit 107 performs PID control (proportional integral derivative control) for the difference. Alternatively, PI control (proportional integral control) is performed, and the control amount is input to the current command unit 101 as a torque command. During the rotation speed control, a torque command based on the speed command from the speed calculation unit 108 is input to the current command unit 101 instead of the torque command from the torque command unit 110.
In the rotational speed control, the target rotational speed of the electric motor 3 is calculated at a constant time interval, and even if the vehicle speed changes suddenly during the shift, the target rotational speed of the shift has a feature that can follow the change in the vehicle speed. Thereby, the shift shock can be reduced.

In FIG. 8, the inverter control circuit 72 is described separately for a speed control unit 73 and a torque control unit 74.
The torque control unit 74 is a part of the inverter control circuit 72 that performs the function of controlling the electric motor 3 by torque control. The current command unit 101, the current PI control unit 102, and the two-phase / three-phase changing unit shown in FIG. 103, a three-phase / two-phase change unit 104, a speed calculation unit 108, and a prediction unit 111.
The speed control unit 73 is a part of the inverter control circuit 72 that performs the function of controlling the electric motor 3 by speed control. The speed control unit 73 includes a comparison unit 109 and a control unit 107. A torque command is given to the unit 101, and the subsequent control is performed by the torque control unit 74.

Next, a shift control device for a vehicle motor drive device in an electric vehicle will be described with reference to the block diagram of FIG. The electric vehicle to be controlled is the electric vehicle described above with reference to FIGS. 1 to 7 to which the shift control method of the above embodiment is applied.
This shift control device for an electric vehicle is a device that implements the shift control method of the above-described embodiment. The shift ECU 61 includes a shift command generation unit 81, a current shift stage clutch release unit 82, a sync control unit 83, A target gear stage clutch engaging means 85 and a rotation speed / torque control switching means 86 are provided. The shift ECU 61 outputs a torque command to the inverter control device 72 as torque control for controlling the electric motor 3 other than during automatic shift, and switches between torque control and rotation speed control during shift.

The shift command generation means 81 generates a shift command to the target shift stage according to a predetermined rule from the accelerator opening signal, the detected vehicle speed value, and the vehicle acceleration / deceleration. This shift command is issued by the shift ECU 61 or the like.
In response to the shift command to the target shift stage, the current shift stage clutch release means 82 operates the shift fork 45 by the shift switching actuator 47 to contact the friction plates 35A, 35B of the current shift stage and the outer wheels 23, 23. Is released, the torque of the electric motor 3 is unloaded by torque control, and the engagement of the roller clutches 16A and 16B at the current gear stage is released.

The sync control means 83 controls the electric motor 3 so as to synchronize so that the rotation speeds of the outer wheels 23 and 23 of the roller clutches 16A and 16B and the inner rings 18A and 18B of the target gear stage are synchronized.
The target gear stage clutch engaging means 85 abuts the friction plates 35A, 35B of the target gear stage and the outer wheels 23, 23, and controls the rotation speed of the electric motor 3, whereby the roller clutches 16A, 16B of the target gear stage are controlled. Engage.
The rotational speed / torque control switching means 86 switches the control of the electric motor 3 from rotational speed control to torque control and inputs the torque of the electric motor 3.

  More specifically, the shift command generating means 81, the current shift speed clutch releasing means 82, the sync control means 83, the target shift speed clutch engaging means 85, and the rotational speed / torque control switching means 86 are more specifically shown in FIG. It has a function of performing the processes of steps S1, S2, S3, S4 and S5, S6.

FIG. 10 is an automatic shift diagram in this shift control method. A solid line is a shift-up line, and a broken line is a shift-down line. The horizontal axis represents the vehicle speed and the vertical axis represents the accelerator opening.
When the accelerator pedal is fully depressed, a downshift is performed and the required acceleration force is obtained. Forcing down the shift down by depressing the accelerator pedal to the fully open position in this way is called kick down. This is the kick-down area in FIG.

  FIG. 11 is a configuration diagram of an upshift automatic shift line map in this shift control method. Data of the shift line map of FIG. 11 is stored in a memory such as a ROM of the shift ECU 61 (FIG. 5). From the shift diagram of FIG. 11, the throttle opening is calculated from the current vehicle speed by referring to the shift map of the upshift of the current shift stage, and compared with the current throttle opening and by the acceleration / deceleration of the vehicle A shift-up shift is executed.

  FIG. 12 is a configuration diagram of a downshift automatic shift line map in this shift control method. Data of the shift line map of FIG. 12 is stored in a memory such as a ROM of the shift ECU 61 (FIG. 5). From the shift diagram of FIG. 12, the throttle opening is calculated from the current vehicle speed by referring to the shift-down shift line map of the current shift stage, and compared with the current throttle opening and the acceleration / deceleration of the vehicle A downshift is performed.

FIG. 13 shows an automatic shift determination flowchart. Automatic shift determination is performed during the D range travel of FIG. Judgment of whether or not automatic shift can be executed is performed in the following three patterns.
Pattern 1: When the vehicle is accelerating, the upshift is performed when the upshift line is crossed from left to right (Q1, Q4, Q5).
Pattern 2: When the vehicle is decelerated, the downshift is performed when crossing the downshift line from right to left (Q1, Q2, Q6, Q7).
Pattern 3: When shifting down from the bottom of the downshift line (during kickdown), a downshift is performed (referred to as kickdown) (Q1, Q2, Q3, Q7).

With respect to an area where automatic shifting is not performed, shifting can be performed manually.
The problem that led to the devising of the automatic shift determination as described above will be described. Based on the conventional accelerator signal and vehicle speed signal alone, the algorithm that determines whether or not automatic shift can be performed does not use the vehicle acceleration / deceleration as a condition for determining whether or not automatic shift can be performed. A hunting phenomenon of gear shifting occurs. According to the above automatic shift determination, such a shift hunting phenomenon can be avoided.

FIG. 14 is a flowchart showing an outline of this shift control method. The execution procedure will be described.
For example, this processing is started by turning on an ignition switch or the like of the vehicle. After the start of this process, in step S1, the accelerator pedal position, the vehicle speed, and the acceleration / deceleration of the vehicle are detected, and the shift ECU 61 issues a shift command. Next, the process proceeds to step S2 (clutch release process), and the shift switching actuator 47 operates the shift member 45 to release the contact between the friction plates 35A and 35B of the current gear stage and the outer ring 23, and at the same time by torque control. Then, the torque of the electric motor 3 is unloaded and the engagement of the roller clutches 16A and 16B at the current gear stage is released.

  Next, in step S3 (synchronization process), the shift ECU 61 synchronizes the rotation speeds of the outer wheels 23 and the inner rings 18A and 18B of the roller clutches 16A and 16B at the target shift speed (synchronization operation), and rotates the rotation speed of the electric motor 3. Accelerate or decelerate by numerical control. In this synchronization process, the release determination of the roller clutches 16A and 16B at the current gear stage is performed twice as described later (FIGS. 15 and 16). When it is determined in the first release determination that the roller clutches 16A and 16B at the current gear stage are released, the second release determination is not performed.

Next, the process proceeds to step S4, where the shift fork 45 is operated by the shift switching actuator 47 to bring the friction plates 35A, 35B of the target shift stage into contact with the outer ring.
In step S5, the speed change ECU 61 performs the rotational speed control divided into two stages, and engages the roller clutches 16A and 16B while controlling the rotational speed of the electric motor 3.
The electric motor 3 is driven by the rotational speed control divided into two stages. Specifically, in the first stage, a large rotational speed difference and a limiting current are set, and in the second stage, a small rotational speed difference and a limiting current are set. As a result, it is possible to engage the clutches 16A and 16B without generating shock torque and noise while shortening the engagement time of the roller clutches 16A and 16B. These steps S4 and S5 correspond to the clutch engagement process.

  Thereafter, the process proceeds to step S6, where the speed change ECU 61 switches the control of the electric motor 3 from the rotation speed control to the torque control, and gives the torque value of the electric motor 3 by n times of interpolation control. In this embodiment, after engaging the roller clutches 16A and 16B of the target gear stage, torque interpolation control is performed by torque control. Since the interpolation control is performed n times, the interpolation value can always track the signal of the accelerator opening. In the tracking process in which the error between the interpolation value and the accelerator opening signal is reduced, if the error falls within a certain threshold value, the tracking operation is completed and the interpolation control is completed n times. Abnormal noise resulting from the backlash of the gears of the reduction gear 5 and torsional shocks such as the shaft hardly occur.

FIG. 15 is a flowchart for determining release of the current gear clutch at the time of downshifting in the shift control method. The method for determining the release of the current gear clutch engagement is the method performed in step S3 of FIG.
However,
Ngi: input rotation speed: rotation speed of electric motor,
Ngo: Output speed: Converted from vehicle speed and gear ratio,
r1: 1st speed reduction ratio,
r2: 2nd speed reduction ratio,
SP: Shift position of shift rod (shift fork) by driving actuator,
SP2f: 2nd gear engagement position,
SP1f: Fastening position of 1st gear,
(The same applies to FIG. 16).

First step: The synchronization operation of the electric motor is started by the rotation speed control (step a1). At this time, the target rotational speed for synchronizing the electric motor is Ngo × r1 + ΔN2. The roller clutch is to be engaged by the difference in rotational speed (converted from ΔN2) between the outer ring and the inner ring of the target gear stage.
However,
ΔN2> 0: The roller clutch of the target gear stage is engaged in the positive direction.
ΔN2 = 0: The roller clutch of the target gear stage is not engaged and is in the neutral position.
ΔN2 <0: The roller clutch of the target gear stage is engaged in the negative direction.
The “positive direction” is a direction in which the roller clutch is fastened when the electric motor is driven. The “negative direction” is a direction in which the roller clutch is engaged when the electric motor is regenerated.
Here, in order to fasten the roller clutch of the target shift stage, the rotational speed difference ΔN2> 0.

Second step: It is determined whether or not a fixed time (Δt1) has elapsed after the start of the synchronization operation (step a2). After a predetermined time (Δt1) has elapsed (step a2: Yes), a first determination is made as to whether or not the engagement of the second-speed clutch has been released (step a3: first release determination process).
Judgment formula: Ngi> Ngo xr2 + ΔN1?
That is, in the first release determination process, the rotational speed Ngi of the electric motor is larger than the rotational speed obtained by adding the constant rotational speed ΔN1 to the rotational speed obtained by multiplying the output rotational speed Ngo by the current gear speed reduction ratio r2. Determine whether or not. The ΔN1 is a rotation speed threshold value. In the case of “large” (step a3: Yes), it is determined that the engagement of the second gear clutch at the current shift stage is released (step a4a), and the release flag is set to “1” and stored in a storage unit (not shown). If “No”, that is, it is determined that the engagement of the second gear clutch at the current gear stage is not released (step a3: No), the release flag is set to “0” and stored in the storage means (step a4b). When it is determined that the roller clutch at the current gear stage is released in the first release determination, the second release determination is not performed.

Third step: It is determined whether or not the synchro operation is completed (step a5: synchro operation completion determination process).
Judgment formula: Ngi ≧ Ngo × r1 + ΔN2?
That is, in the process of determining the completion of the synchro operation, it is determined whether or not the rotational speed Ngi of the electric motor is equal to or higher than the rotational speed obtained by multiplying the output rotational speed Ngo by the reduction gear ratio r1 of the target shift speed and a certain rotational speed ΔN2. to decide. When the rotation speed is equal to or higher than the rotation speed (step a5: Yes), it is determined that the synchronization operation is completed, and this process is terminated. If “No”, that is, it is determined that the synchronization operation is being performed (step a5: No), the process proceeds to the fourth step.

Fourth step: It is determined whether or not a certain time (Δt2) has elapsed (step a6), and when it has not elapsed (step a6: No), the process returns to the third step. After a predetermined time (Δt2) has elapsed (step a6: Yes), it is determined whether or not the release flag is “1” (step a7). When the release flag = “1” (step a7: Yes), the third step is performed. Return. When it is determined that the release flag is not “1” (step a7: No), a second determination is made as to whether or not the engagement of the second-speed clutch is released (step a8: second release determination process). .
Judgment formula: Ngi> Ngo xr2 + ΔN1?
In this second release determination process, the rotational speed Ngi of the electric motor is greater than the rotational speed obtained by adding the constant rotational speed ΔN1 to the rotational speed obtained by multiplying the output rotational speed Ngo by the reduction ratio r2 of the current gear. If it is determined as “large”, the process returns to the third step. When it is determined that the engagement of the second gear clutch at the current gear stage has not been released (step a8: No), the process proceeds to the fifth step.

  Fifth step: There is a possibility that the engagement of the roller clutch 16B at the current gear stage has not been released. Therefore, the shift switching actuator 47 is immediately stopped (step a9), the electric motor control is switched to torque control (step a10), and zero torque (T = 0) is set. By driving the shift switching actuator 47, the shift member 45 is pulled back in the SP2f direction (step a11). As a result, an excessive load is not applied to the roller clutch 16B.

FIG. 16 is a flowchart for determining release of the current gear clutch at the time of upshifting in the shift control method. The method for determining the release of the current gear clutch engagement is the method performed in step S3 of FIG.
First step: The synchronization operation of the electric motor is started by the rotation speed control (step a1). At this time, the target rotational speed for synchronizing the electric motor is Ngo × r2 + ΔN2. The roller clutch is to be engaged by the difference in rotational speed (converted from ΔN2) between the outer ring and the inner ring of the target gear stage. In order to engage the roller clutch of the target gear stage, the rotational speed difference ΔN2> 0.

Second step: When a certain time (Δt1) has elapsed after the start of the synchronization operation (step a2: Yes), a first determination is made as to whether or not the first-speed clutch is disengaged (step a3: second). 1 cancellation judgment process).
Judgment formula: Ngi <Ngo xr1-ΔN1?
That is, in the first release determination process, the rotational speed Ngi of the electric motor is smaller than the rotational speed obtained by multiplying the output rotational speed Ngo by the reduction ratio r1 of the current gear stage and the constant rotational speed ΔN1. Judge whether or not. In the case of “small” (step a3: Yes), it is determined that the engagement of the first speed clutch at the current shift stage is released (step a4a), and the release flag is set to “1” and stored in the storage means. When it is determined that the roller clutch at the current gear stage is released in the first release determination, the second release determination is not performed.

Third step: It is determined whether or not the synchro operation is completed (step a5: synchro operation completion determination process).
Judgment formula: Ngi ≦ Ngo × r2 + ΔN2?
That is, in the process of determining the completion of the synchro operation, it is determined whether or not the rotational speed Ngi of the electric motor is equal to or lower than the rotational speed obtained by adding the constant rotational speed ΔN2 to the rotational speed obtained by multiplying the output rotational speed Ngo by the reduction gear ratio r2 of the target gear. to decide. When the rotational speed is equal to or lower than the rotation speed (step a5: Yes), it is determined that the synchronization operation is completed, and this process is terminated. If “No”, that is, it is determined that the synchronization operation is being performed (step a5: No), the process proceeds to the fourth step.

Fourth step: It is determined whether or not a certain time (Δt2) has elapsed. If not (step a6: No), the process returns to the third step. After a certain time (Δt2) has elapsed (step a6: Yes), it is determined whether or not the release flag is “1”. When the release flag = “1” (step a7: Yes), the process returns to the third step. If it is determined that the release flag is not “1” (step a7: No), a second determination is made as to whether or not the engagement of the first-speed clutch has been released (step a8: second release determination process). .
Judgment formula: Ngi <Ngo xr1-ΔN1?
In this second release determination process, the rotational speed Ngi of the electric motor is smaller than the rotational speed obtained by subtracting the constant rotational speed ΔN1 from the rotational speed obtained by multiplying the output rotational speed Ngo by the reduction ratio r1 of the current gear. Is determined, the process returns to the third step. If it is determined that the engagement of the first gear clutch at the current gear stage has not been released (step a8: No), the process proceeds to the fifth step.

  Fifth step: There is a possibility that the engagement of the roller clutch 16A at the current gear stage has not been released. Therefore, the shift switching actuator 47 is immediately stopped (step a9), the control of the electric motor 3 is switched to torque control (step a10), and zero torque (T = 0) is set. By driving the shift switching actuator 47, the shift member 45 is pulled back in the SP1f direction (step a11). This prevents an unreasonable load from acting on the roller clutch 16A.

Next, details of the vehicle motor drive device of FIGS. 3 and 4 will be described with reference to FIGS.
In FIG. 3, the motor shaft 4 is coaxially arranged in series with the input shaft 7, and is rotationally driven by a stator 12 of the electric motor 3 fixed to the housing 11. The input shaft 7 is rotatably supported by a pair of opposed bearings 13 incorporated in the housing 11, and the shaft end of the input shaft 7 is connected to the motor shaft 4 by spline fitting. The output shaft 8 is rotatably supported by a pair of opposed bearings 14 incorporated in the housing 11.

  The first-speed input gear 9 </ b> A and the second-speed input gear 9 </ b> B are arranged at an interval in the axial direction, and are fixed to the input shaft 7 so as to rotate integrally with the input shaft 7 about the input shaft 7. The first-speed output gear 10A and the second-speed output gear 10B are also arranged at intervals in the axial direction.

  As shown in FIG. 4, the first-speed output gear 10 </ b> A is formed in an annular shape that penetrates the output shaft 8, and is supported by the output shaft 8 via a bearing 15, and the output shaft 8 is centered on the output shaft 8. And can be rotated. Similarly, the second speed output gear 10 </ b> B is also rotatably supported by the output shaft 8 via the bearing 15.

  The first speed input gear 9A and the first speed output gear 10A mesh with each other, and rotation is transmitted between the first speed input gear 9A and the first speed output gear 10A. The 2nd speed input gear 9B and the 2nd speed output gear 10B are also meshed, and rotation is transmitted between the 2nd speed input gear 9B and the 2nd speed output gear 10B by the meshing. The reduction ratio between the second speed input gear 9B and the second speed output gear 10B is smaller than the reduction ratio between the first speed input gear 9A and the first speed output gear 10A.

  Between the first-speed output gear 10A and the output shaft 8, a first-speed two-way roller clutch 16A that incorporates torque transmission and switching between the first-speed output gear 10A and the output shaft 8 is incorporated. Further, a 2-speed 2-way roller clutch 16B is incorporated between the 2-speed output gear 10B and the output shaft 8 to switch torque transmission and interruption between the 2-speed output gear 10B and the output shaft 8. .

  Since the first-speed two-way roller clutch 16A and the second-speed two-way roller clutch 16B have the same symmetrical configuration, the second-speed two-way roller clutch 16B will be described below. The parts corresponding to the 2-speed 2-way roller clutch 16B are denoted by the same reference numerals or the reference numerals in which the alphabet B at the end is replaced with A, and the description thereof is omitted.

  As shown in FIGS. 17 to 19, the two-speed two-way roller clutch 16 </ b> B includes a cylindrical surface 17 provided on the inner periphery of the second-speed output gear 10 </ b> B and an annular second gear that is prevented from rotating on the outer periphery of the output shaft 8. It comprises a cam surface 19 formed on the cam member 18B, a roller 20 incorporated between the cam surface 19 and the cylindrical surface 17, a second speed holder 21B for holding the roller 20, and a second speed switch spring 22B. The cam surface 19 is a surface that forms a wedge-shaped space S that gradually narrows from the center in the circumferential direction toward both ends in the circumferential direction with the cylindrical surface 17. For example, the cam surface 19 faces the cylindrical surface 17 as shown in FIG. It is a flat surface.

  As shown in FIGS. 4 and 22, the 2-speed retainer 21 </ b> B includes a cylindrical portion 24 in which a plurality of pockets 21 a that store the rollers 20 are formed at intervals in the circumferential direction, and a radial direction from one end of the cylindrical portion 24. And an inward flange portion 25 extending inward. The radially inner end of the inward flange portion 25 is supported so as to be slidable in the circumferential direction on the outer periphery of the second-speed cam member 18B, and the second-speed cage 21B causes the cam surface 19 and the cylindrical surface 17 to slide. Between the engagement position where the roller 20 is engaged and the neutral position where the engagement of the roller 20 is released, rotation relative to the output shaft 8 is possible. Further, the inward flange portion 25 of the second-speed cage 21B is restricted from moving in the axial direction, thereby making the second-speed cage 21B immovable in the axial direction.

  As shown in FIG. 18, each cam surface 19 is formed symmetrically with respect to a virtual plane including the center of rotation, so that the rollers 20 arranged between each cam surface 19 and the cylindrical surface 17 can rotate forward. The engagement is possible in both the direction and the reverse direction. That is, when the vehicle is advanced by the torque generated by the electric motor 3, the roller 20 held by the second-speed cage 21B is rotated by rotating the second-speed cage 21B in the normal rotation direction with respect to the output shaft 8. Is engaged with a space narrowing portion on the forward rotation direction side between the cam surface 19 and the cylindrical surface 17, and torque in the forward rotation direction is transmitted between the second speed output gear 9 </ b> B and the output shaft 8 via the roller 20. On the other hand, when the vehicle is moved backward by the torque generated by the electric motor 3, the second speed retainer 21B is rotated relative to the output shaft 8 in the reverse rotation direction to maintain the second speed. The roller 20 held by the vessel 21B is engaged with the space narrowing portion on the reverse direction side between the cam surface 19 and the cylindrical surface 17, and between the second-speed output gear 9B and the output shaft 8 via the roller 20. Transmit torque in reverse direction It is possible to be.

  As shown in FIGS. 19 and 22, the two-speed switch spring 22 </ b> B includes a C-shaped annular portion 26 in which a steel wire is wound in a C shape, and a pair extending radially outward from both ends of the C-shaped annular portion 26. Extending portions 27, 27. The C-shaped annular portion 26 is fitted into a circular switch spring accommodating recess 28 formed on the axial end surface of the second-speed cam member 18B, and the pair of extending portions 27 and 27 are axial end surfaces of the second-speed cam member 18B. It is inserted in the radial groove 29 formed in.

  The radial groove 29 is formed so as to extend radially outward from the inner peripheral edge of the switch spring accommodating recess 28 and reach the outer periphery of the second-speed cam member 18B. The extension portion 27 of the second speed switch spring 22B protrudes from the radially outer end of the radial groove 29, and the protruding portion of the extension portion 27 from the radial groove 29 is the cylindrical portion of the second speed cage 21B. 24 is inserted into a notch 30 formed at the end in the axial direction. The radial groove 29 and the notch 30 are formed to have the same width.

  The extending portions 27, 27 are in contact with the inner surface facing the circumferential direction of the radial groove 29 and the inner surface facing the circumferential direction of the notch 30, respectively, and 2 by the circumferential force acting on the contact surface. The speed holder 21B is elastically held in the neutral position.

  That is, when the second-speed cage 21B is rotated relative to the output shaft 8 and moved in the circumferential direction from the neutral position shown in FIG. 19, the position of the radial groove 29 and the position of the notch 30 are shifted in the circumferential direction. Therefore, the C-shaped annular portion 26 is elastically deformed in the direction in which the distance between the pair of extending portions 27, 27 is narrowed, and the pair of extending portions 27, 27 of the two-speed switch spring 22B are caused to be radially grooved 29 by the elastic restoring force. The inner surface of the notch 30 and the inner surface of the notch 30 are pressed, and a force in a direction to return the second-speed cage 21B to the neutral position is applied by the pressing.

  As shown in FIG. 4, the first-speed cam member 18A and the second-speed cam member 18B are prevented from rotating with respect to the output shaft 8 by spline fitting. The cam surface 19 of the first speed cam member 18A and the cam surface 19 of the second speed cam member 18B have the same number and the same phase. Further, the first speed cam member 18 </ b> A and the second speed cam member 18 </ b> B are non-movable in the axial direction by a pair of retaining rings 31 fitted to the outer periphery of the output shaft 8. A spacer 32 is incorporated between the first speed cam member 18A and the second speed cam member 18B.

  The first-speed two-way roller clutch 16A and the second-speed two-way roller clutch 16B can be selectively engaged by the speed change actuator 33.

  As shown in FIG. 17, the speed change actuator 33 includes a shift ring 34 movably provided in the axial direction between the first speed output gear 10A and the second speed output gear 10B, and the first speed output gear 10A and the shift ring 34. A first-speed friction plate 35A incorporated in between, and a second-speed friction plate 35B incorporated between the second-speed output gear 10B and the shift ring 34.

  Here, since the first-speed friction plate 35A and the second-speed friction plate 35B have the same configuration with left-right symmetry, the second-speed friction plate 35B will be described below, and the first-speed friction plate 35A corresponds to the second-speed friction plate 35B. Parts are denoted by the same reference numerals or reference numerals in which the alphabet B at the end is replaced with A, and description thereof is omitted.

  The second-speed friction plate 35B is provided with a projecting piece 36 that engages with the notch 30 of the second-speed retainer 21B. The engagement between the projecting piece 36 and the notch 30 causes the second-speed friction plate 35B to hold the second speed. The rotation is stopped by the vessel 21B. The notch 30 of the second-speed retainer 21B accommodates the projecting piece 36 of the second-speed friction plate 35B so as to be slidable in the axial direction. By this sliding, the second-speed friction plate 35B rotates around the second-speed retainer 21B. It can move in the axial direction with respect to the second-speed retainer 21B between a position in contact with the side surface of the second-speed output gear 10B and a position away from the second-speed output gear 10B.

  A recess 37 is formed at the tip of the projecting piece 36 of the second speed friction plate 35 </ b> B, and a protrusion 38 that engages with the recess 37 is formed on the outer periphery of the spacer 32. The concave portion 37 and the convex portion 38 are engaged with the concave portion 37 and the convex portion 38 in a state where the second speed friction plate 35B is located away from the side surface of the second speed output gear 10B. Is prevented from rotating around the output shaft 8 via the spacer 32. At this time, the second-speed retainer 21B, which is prevented from rotating by the second-speed friction plate 35B, is held in the neutral position. Further, in a state where the second speed friction plate 35B is in a position in contact with the side surface of the second speed output gear 10B, the engagement between the concave portion 37 and the convex portion 38 is released to release the rotation prevention of the second speed friction plate 35B. It has become so.

  Between the second speed friction plate 35B and the second speed cam member 18B, a second speed separation spring 39B is incorporated in an axially compressed state, and the second speed friction plate is generated by the elastic restoring force of the second speed separation spring 39B. 35B is urged in a direction away from the side surface of the second-speed output gear 10B.

  The second speed separating spring 39B is a coil spring wound along the outer periphery of the spacer 32, and one end thereof is supported by the end face in the axial direction of the second speed cam member 18B via the second speed washer 39B. The 2-speed washer 39B is formed in an annular shape so as to cover the radial groove 29 on the axial end surface of the 2-speed cam member 18B.

  The shift ring 34 presses the first-speed friction plate 35A to contact the side surface of the first-speed output gear 10A and the first-speed shift position SP1f to press the second-speed friction plate 35B to contact the side surface of the second-speed output gear 10B. The second-speed shift position SP2f is supported so as to be movable in the axial direction. Further, a shift mechanism 41 that moves the shift ring 34 in the axial direction between the first-speed shift position SP1f and the second-speed shift position SP2f is provided. The shift mechanism 41 constitutes a part of the gear ratio switching mechanism 40 as described above.

  As shown in FIGS. 20 and 21, the shift mechanism 41 is related to a shift sleeve 43 that rotatably supports the shift ring 34 via a rolling bearing 42, and an annular groove 44 provided on the outer periphery of the shift sleeve 43. The two-forked shift fork 45, the shift rod 46 to which the shift fork 45 is fixed, the shift switching actuator 47 that is a shift motor, and the motion conversion that converts the rotation of the shift switching actuator 47 into the linear motion of the shift rod 46. It consists of a mechanism 48 (feed screw mechanism or the like).

  As shown in FIG. 21, the shift rod 46 is arranged parallel to the output shaft 8 at a distance, and is supported by a pair of sliding bearings 49 incorporated in the housing 11 so as to be slidable in the axial direction. . The rolling bearing 42 incorporated between the shift ring 34 and the shift sleeve 43 is assembled so as to be immovable in the axial direction with respect to both the shift ring 34 and the shift sleeve 43.

  In the shift mechanism 41, the rotation of the shift switching actuator 47 is converted into a linear motion by the motion conversion mechanism 48 and transmitted to the shift fork 45, and the linear motion of the shift fork 45 is transmitted to the shift ring 34 via the rolling bearing 42. By doing so, the shift ring 34 is moved in the axial direction.

  As shown in FIG. 17, a preload spring 50 that is compressible in the axial direction is incorporated in the axial clearance on both sides between the shift fork 45 and the annular groove 44. Thus, when the first speed friction plate 35A is pressed by the shift ring 34 and brought into contact with the side surface of the first speed output gear 10A, the preload spring 50 is adjusted by adjusting the relative position in the axial direction of the shift fork 45 with respect to the shift sleeve 43. Thus, it is possible to adjust the friction force between the contact surfaces of the first speed friction plate 35A and the first speed output gear 10A. Further, also when the second speed friction plate 35B is pressed by the shift ring 34 and brought into contact with the side surface of the second speed output gear 10B, the frictional force between the contact surfaces of the second speed friction plate 35B and the second speed output gear 10B is adjusted. Is possible.

  As shown in FIG. 3, a differential drive gear 51 that transmits the rotation of the output shaft 8 to the differential 6 is fixed to the output shaft 8.

  The differential 6 includes a differential case 53 rotatably supported by a pair of bearings 52, a ring gear 54 that is fixed to the differential case 53 coaxially with the rotational center of the differential case 53, and meshes with the differential drive gear 51, and the rotational center of the differential case 53. The pinion shaft 55 is fixed to the differential case 53 in a perpendicular direction, the pair of pinions 56 is rotatably supported by the pinion shaft 55, and the pair of left and right side gears 57 that mesh with the pair of pinions 56. The left side gear 57 is connected to the shaft end portion of the axle 58 connected to the left wheel, and the right side gear 57 is connected to the shaft end portion of the axle 58 connected to the right wheel. When the output shaft 8 rotates, the rotation of the output shaft 8 is transmitted to the differential case 53 via the differential drive gear 51, and the rotation of the differential case 53 is distributed to the left and right wheels via the pinion 56 and the side gear 57.

Below, the operation example of the motor drive apparatus A for vehicles is demonstrated.
First, as shown in FIG. 17, when the first speed friction plate 35A is separated from the side surface of the first speed output gear 10A and the second speed friction plate 35B is also separated from the side surface of the second speed output gear 10B, the first speed holding is performed. 21A is held in the neutral position by the elastic force of the first speed switch spring 22A, and the second speed holder 21B is also held in the neutral position by the elastic force of the second speed switch spring 22B. The engagement of the roller 20 is released, and the 2-speed 2-way roller clutch 16B is also released from the engagement of the roller 20.

  In this state, even if the input shaft 7 is rotated by driving the electric motor 3 shown in FIG. 3, transmission of rotation is interrupted by the first-speed two-way roller clutch 16A and the second-speed two-way roller clutch 16B. The first speed output gear 10 </ b> A and the second speed output gear 10 </ b> B idle, and the rotation of the input shaft 7 is not transmitted to the output shaft 8.

  Next, when the shift mechanism 41 is operated and the shift ring 34 shown in FIG. 17 is moved toward the first-speed output gear 10A, the first-speed friction plate 35A comes into contact with the side surface of the first-speed output gear 10A. The first-speed friction plate 35A rotates relative to the output shaft 8 by the frictional force between the surfaces, and the first-speed retainer 21A that is prevented from rotating by the first-speed friction plate 35A resists the elastic force of the first-speed switch spring 22A. The roller 20 held by the first-speed holder 21A is pushed into the narrowed portion of the wedge-shaped space S between the cylindrical surface 17 and the cam surface 19 and engaged. Become.

  In this state, the rotation of the first-speed output gear 10A is transmitted to the output shaft 8 via the first-speed two-way roller clutch 16A, and the rotation of the output shaft 8 is transmitted to the axle 58 via the differential 6. As a result, in the electric vehicle EV shown in FIG. 1, the front wheels 1 as drive wheels are rotationally driven, and in the hybrid vehicle HV shown in FIG. 2, the rear wheels 2 as auxiliary drive wheels are rotationally driven.

  Next, when the shift ring 34 is moved in the axial direction from the first speed shift position to the second speed shift position by the operation of the shift mechanism 41, the frictional force between the contact surfaces of the first speed friction plate 35A and the first speed output gear 10A. Therefore, the first-speed retainer 21A is moved from the engagement position to the neutral position by the elastic force of the first-speed switch spring 22A, and the first-speed two-way roller clutch 16A is engaged by the movement of the first-speed retainer 21A. Is released.

  When the shift ring 34 reaches the 2nd speed shift position, the 2nd speed friction plate 35B is pressed by the shift ring 34 and comes into contact with the side surface of the 2nd speed output gear 10B. The second-speed retainer 21B that rotates relative to the output shaft 8 and is prevented from rotating by the second-speed friction plate 35B moves from the neutral position to the engagement position against the elastic force of the second-speed switch spring 22B. The roller 20 held by the speed holder 21 </ b> B is pushed into and engaged with the narrowed portion of the wedge-shaped space S between the cylindrical surface 17 and the cam surface 19.

  In this state, the rotation of the 2-speed output gear 10B is transmitted to the output shaft 8 via the 2-speed 2-way roller clutch 16B, and the rotation of the output shaft 8 is transmitted to the axle 58 via the differential 6.

  Similarly, by shifting the shift ring 34 in the axial direction from the 2nd gear shift position to the 1st gear shift position, the engagement of the 2nd gear 2 way roller clutch 16B is released and the 1st gear 2 way roller clutch 16A is engaged. Can be combined.

  When the first-speed two-way roller clutch 16A is disengaged, if torque is transmitted via the first-speed two-way roller clutch 16A, the torque causes the roller 20 to move between the cylindrical surface 17 and the cam surface 19. Acting to push into the narrowed portion of the wedge-shaped space S between the two, the disengagement of the first-speed two-way roller clutch 16A is prevented. Therefore, when the shift ring 34 starts to move in the axial direction from the first speed shift position SP1f to the second speed shift position SP2f by the operation of the shift mechanism 41, the first speed friction plate 35A is moved to the side surface of the first speed output gear 10A. There is a possibility that the engagement of the first-speed two-way roller clutch 16A is not released even though it has already separated from the initial position.

  Therefore, in order to reliably disengage the first-speed two-way roller clutch 16A, not only the first-speed friction plate 35A is separated from the side surface of the first-speed output gear 10A by the operation of the shift mechanism 41, but also the electric It is necessary to change the torque transmitted between the input shaft 7 and the output shaft 8 by controlling the output of the motor 3. The same applies when the second-speed two-way roller clutch 16B is disengaged.

  Therefore, in the above control system, the electric motor 3 and the gear change actuator 47 are controlled by the gear change control device shown in FIG. 9, and the engagement of the first-speed two-way roller clutch 16A or the second-speed two-way roller clutch 16B is controlled by this control. The reliability of the operation when releasing the connection is secured.

According to the shift control method described above, if it is determined that the engagement of the current shift stage is once released in the first release determination process, then, for example, when the rotation speed of the electric motor 3 fluctuates. In addition, it is possible to reliably prevent erroneous determination that the engagement of the current shift speed is not released. As a result, it is possible to prevent the synchronization operation from being performed again, shorten the speed change time, and prevent energy consumption.
In the first release determination process, when it is determined that the engagement of the roller clutches 16A and 16B at the current gear stage has been released, the determination of the engagement release in the second release determination process is not performed. The determination in the second release determination process can be omitted, and the shift time can be shortened reliably.

  In the sync operation completion determination process, it is determined that the sync operation has not been completed, and in the second release determination process, the disengagement determination is performed, and in the determination that the sync operation is completed, the second release determination is performed. The determination of disengagement in the process is not performed. Thus, after the first release determination process, before the second release determination process, the synchronization operation completion determination process is determined. When the synchronization operation is completed, the synchronization process can be preferentially terminated, and the next clutch engagement process can be shifted without delay.

  In the synchronization process, the synchronization operation of the electric motor 3 is continued regardless of the determination result of the first release determination process. In this case, the electric motor 3 can be smoothly synchronized, and the change rate of the rotation speed in the electric motor 3 can be reduced. As a result, it is possible to make it difficult for abnormal noise caused by backlash between the gears.

DESCRIPTION OF SYMBOLS 3 ... Electric motor 4 ... Motor shaft 5 ... Transmission 7 ... Input shaft 16A, 16B ... Roller clutch 18A, 18B ... Inner ring 19 ... Cam surface 20 ... Roller 21A, 21B ... Cage 23 ... Outer ring 35A, 35B ... Friction plate 40 ... gear ratio switching mechanism 45 ... shift member 47 ... gear change actuator 82 ... current gear clutch release means 83 ... sync control means 85 ... target gear clutch engagement means 86 ... speed / torque control change means LA, LB ... gears Row S ... wedge-shaped space

Claims (8)

Intermittent switching between a gear train of a plurality of gear stages having different gear ratios, an input shaft connected to a motor shaft that is an output shaft of an electric motor for traveling, and a gear train of each gear stage A two-way roller clutch for each gear stage capable of shifting, and a transmission having a gear ratio switching mechanism for switching between on and off of each roller clutch,
Each roller clutch is in a connected state when a roller is interposed in each wedge-shaped space provided between the cam surface of the inner ring and the outer ring, and each roller engages with a narrowed portion of the wedge-shaped space. It is configured to be in a cut state by being positioned in the spread part of the wedge-shaped space,
The transmission ratio switching mechanism is a mechanism that switches contact and separation of a rotating friction plate connected to a retainer with an outer ring by advancing and retreating a shift member by a transmission switching actuator.
In a shift control method for an electric vehicle,
A clutch release process in which the shift member is operated by the shift switching actuator in response to a shift command to the target shift stage, the torque of the electric motor is unloaded, and the roller clutch of the current shift stage is released; ,
A synchronization process for synchronizing the rotation speed of the outer ring and the inner ring of the roller clutch of the target gear stage by synchronizing the rotation speed of the electric motor;
A clutch engagement process for engaging the roller clutch of the target gear stage by bringing the friction plate of the target gear stage into contact with the outer ring and controlling the rotational speed of the electric motor;
Have
After the clutch release process, the sync process includes:
A first release determination step of determining whether or not the engagement of the roller clutch at the current gear stage has been released after a lapse of a certain time since the start of the synchronization operation for increasing or decreasing the rotation speed of the electric motor;
In the first release determination process, if it is determined that at least the engagement of the roller clutch at the current shift stage has not been released, the engagement of the roller clutch at the current shift stage is released after a predetermined time has passed. A second release determination process for determining whether or not
A shift control method for an electric vehicle, comprising:   2. The electric vehicle according to claim 1, wherein in the first release determination process, when it is determined that the engagement of the roller clutch at the current shift stage is released, the determination of the engagement release in the second release determination process is not performed. Shift control method.   2. The electric device according to claim 1, wherein, in the first release determination process, when it is determined that the engagement of the roller clutch at the current shift stage is not released, the determination of the engagement release in the second release determination process is performed. Shift control method for automobile.   4. The method according to claim 3, wherein when it is determined in the first release determination process that the engagement of the current speed roller clutch is not released, before the engagement release determination is performed in the second release determination process. A synchronization operation completion determination process for determining whether or not the synchronization operation of the electric motor has been completed. In the synchronization operation completion determination process, the second release is determined by determining that the synchronization operation has not been completed. A shift control method for an electric vehicle in which determination of disengagement in the determination process is performed, and determination of disengagement in the second disengagement determination process is not performed based on the determination that the synchronization operation is completed.   5. The shift control method for an electric vehicle according to claim 1, wherein, in the synchronization process, the synchronization operation of the electric motor is continued regardless of the determination result of the first release determination process. 6.   6. The rotation speed of the electric motor according to claim 1, wherein at the time of downshifting, the rotation speed of the electric motor is obtained by adding a constant rotation speed to a rotation speed obtained by multiplying an output rotation speed by a reduction ratio of the current gear stage. An electric vehicle shift control method for determining that the engagement of the roller clutch at the current shift stage is released only when the number is larger than the number.   The rotation speed of the electric motor according to any one of claims 1 to 6, wherein, when shifting up, the rotation speed of the electric motor is obtained by subtracting a fixed rotation speed from a rotation speed obtained by multiplying the output rotation speed by the reduction gear ratio of the current gear. The electric vehicle shift control method for determining that the engagement of the roller clutch at the current shift stage is released only when the number is smaller than the number. Intermittent switching between a gear train of a plurality of gear stages having different gear ratios, an input shaft connected to a motor shaft that is an output shaft of an electric motor for traveling, and a gear train of each gear stage A two-way roller clutch for each gear stage capable of shifting, and a transmission having a gear ratio switching mechanism for switching between on and off of each roller clutch,
Each roller clutch is in a connected state when a roller is interposed in each wedge-shaped space provided between the cam surface of the inner ring and the outer ring, and each roller engages with a narrowed portion of the wedge-shaped space. It is configured to be in a cut state by being positioned in the spread part of the wedge-shaped space,
The transmission ratio switching mechanism is a mechanism that switches contact and separation of a rotating friction plate connected to a retainer with an outer ring by advancing and retreating a shift member by a transmission switching actuator.
A shift control device for an electric vehicle,
In response to a shift command to a target shift stage, the shift member is operated by the shift switching actuator to unload the torque of the electric motor and release the engagement of the roller clutch of the current shift stage. Release means,
Synchronization control means for synchronizing the rotation speed of the outer ring and the inner ring of the roller clutch at the target gear stage by synchronizing the rotation speed of the electric motor;
Target gear stage clutch engagement means for engaging a roller clutch of the target gear stage by bringing the friction plate of the target gear stage into contact with the outer ring and controlling the rotational speed of the electric motor;
Have
The synchronization control means includes
A first release determination means for determining whether or not the engagement of the roller clutch at the current gear stage has been released after a lapse of a certain time since the start of the synchronization operation for increasing or decreasing the rotation speed of the electric motor;
When it is determined by the first release determination means that at least the engagement of the roller clutch at the current shift stage has not been released, the engagement of the roller clutch at the current shift stage is released after a predetermined time has passed. Second release determination means for determining whether or not
A shift control apparatus for an electric vehicle, comprising:

Images