JP6818619B2 - Parking lock controller - Google Patents

Description

The present invention relates to a parking lock control device.

In a vehicle equipped with a parking lock mechanism, when the parking range is selected by the shift lever, the parking gear is engaged by engaging the parking pole with the parking gear provided on the power transmission shaft that transmits power to the drive wheels by the parking lock mechanism. (Power transmission shaft) is locked.

For example, in Patent Document 1, the power output from the output shaft of the electric motor is decelerated by the speed reducer, and the decelerated power is distributed to the left and right drive systems by the planetary gear type differential device, and the left and right drive wheels. The electric vehicle transmitted to is disclosed. In this electric vehicle, a parking gear is spline-fitted to the output shaft of the electric motor, and when the parking range is selected by the shift lever, the parking pole is rotated toward the parking gear, and the parking pole meshes with the parking gear. The rotation of the output shaft is mechanically blocked.

JP-A-6-276607

However, in the technique disclosed in Patent Document 1, depending on the stop position of the output shaft of the electric motor, when the parking pole is rotated to the parking gear side, the claws of the parking pole hit the teeth of the parking gear and the parking pole is pressed. It may not mesh with the parking gear. If the parking pole is not engaged with the parking gear, for example, if the vehicle stops on a slope and the side brake is not operated and the brake pedal is released after the driver selects the parking range, parking The parking gear (output shaft of the electric motor) may rotate until the pole engages the parking gear, and the vehicle may slide down on a slope.

The present invention has been made to solve the above problems, and in a vehicle provided with an electric motor as a drive source, it is possible to prevent the vehicle from slipping down after the parking range is selected while suppressing the cost. It is an object of the present invention to provide a possible parking lock control device.

The parking lock control device according to the present invention is a parking lock control device mounted on a vehicle provided with an electric motor as a drive source, and is a parking gear provided on a power transmission shaft for transmitting power generated by the electric motor, and a claw. A parking pole that locks the parking gear by engaging the claw with the tooth groove between the teeth of the parking gear, and parking when the rotation of the electric motor is stopped due to the deceleration during deceleration of the vehicle. The position of the gear groove is estimated, and based on the estimated position of the parking gear tooth groove, when the rotation of the electric motor is stopped, the claw of the parking pole meshes with the tooth groove of the parking gear. It is characterized by including a stop meshing position determining means for determining the meshing position and a control means for controlling the electric motor so that the parking gear stops at the stop meshing position determined by the stop meshing position determining means. To do.

In the parking lock control device according to the present invention, when the rotation of the electric motor is stopped during deceleration of the vehicle, the claws of the parking pole mesh with the tooth groove to determine the meshing position when the parking range is stopped. Then, in the parking lock control device according to the present invention, the control means drives and controls the electric motor so that the parking gear stops at the stop meshing position, and stops the parking gear (power transmission shaft) at the stop mesh position. By adjusting the position of the parking gear when the electric motor (vehicle) is stopped in this way, the parking range is selected by the driver's shift lever operation, and when the parking pole moves to the parking gear side, parking is performed. The claws of the pole mesh with the tooth groove of the parking gear. As a result, for example, when the vehicle stops on a slope, even if the side brake is not operated after the parking range is selected and the brake pedal is released, the claws of the parking pole mesh with the tooth grooves of the parking gear. Therefore, the power transmission shaft is locked and the vehicle does not slide down on a slope. In order to adjust the stop position of the parking gear, the electric motor of the drive source mounted on the vehicle and the control means of the electric motor are used, so that it is not necessary to separately provide the adjusting means. As described above, according to the parking lock control device according to the present invention, in a vehicle provided with an electric motor as a drive source, it is possible to prevent the vehicle from sliding down after the parking range is selected while suppressing the cost. Become.

In the parking lock control device according to the present invention, it is preferable that the stop meshing position determining means determines the meshing position in front of the estimated tooth groove position of the parking gear as the stop meshing position. With this configuration, the rotation angle of the electric motor until it stops is smaller than when the electric motor is not controlled, and the braking distance of the vehicle is not extended.

In the parking lock control device according to the present invention, the tooth groove position acquisition means for acquiring the position of the tooth groove of the parking gear, the angular velocity acquisition means for acquiring the angular velocity of the parking gear, and the angular acceleration acquisition for acquiring the angular acceleration of the parking gear. The means for determining the meshing position at the time of stopping includes the means, the position of the tooth groove acquired by the tooth groove position acquisition means, and the angular velocity and the angle acquired by the angular velocity acquisition means when the position of the tooth groove is acquired. It is preferable to determine the meshing position at the time of stopping by using the angular acceleration acquired by the acceleration acquisition means. With this configuration, the time and rotation angle required for the rotation of the electric motor to stop can be obtained by using the angular velocity and angular acceleration of the parking gear. Therefore, these values and the position of the tooth groove of the parking gear ( For example, by using the position relative to the position of the claw of the parking pole), the position of the tooth groove of the parking gear when the rotation of the electric motor is stopped can be estimated accurately, and the meshing position at the time of stopping can be accurately determined. ..

The parking lock control device according to the present invention includes a gradient acquisition means for acquiring the slope of the road surface, and the control means is in a meshing position when the parking gear is stopped when the gradient acquired by the gradient acquisition means is equal to or higher than a predetermined gradient. It is preferable to control the electric motor so as to stop at. With such a configuration, it is possible to prevent the vehicle from sliding down on a slope having a slope equal to or higher than a predetermined slope.

The parking lock control device according to the present invention includes a deceleration acquisition means for acquiring the deceleration of the vehicle, and the control means is a parking gear when the deceleration acquired by the deceleration acquisition means is equal to or less than a predetermined deceleration. It is preferable to control the electric motor so that the motor stops at the meshing position when stopped. With this configuration, when the deceleration exceeds a predetermined deceleration, the control for adjusting the stop position of the parking gear (control of the stop position with respect to the electric motor) is not performed, so that the driver can operate the brake. The vehicle can be stopped accordingly.

In the parking lock control device according to the present invention, the tooth groove position acquisition means acquires the position of the tooth groove of the parking gear by using the rotation angle acquired by the rotation angle acquisition means for acquiring the rotation angle of the rotor of the electric motor. Is preferable. With this configuration, the rotation angle acquisition means for the electric motor of the drive source is used as the tooth groove position acquisition means, so that it is not necessary to separately provide the tooth groove position acquisition means, and the cost can be suppressed. ..

According to the present invention, in a vehicle provided with an electric motor as a drive source, it is possible to prevent the vehicle from slipping down after the parking range is selected while suppressing the cost.

It is a block diagram which shows the structure of the parking lock control device which concerns on embodiment. It is a perspective view which shows the structure of the parking lock mechanism controlled by the parking lock control device which concerns on embodiment. It is explanatory drawing of the method of determining the meshing position at the time of stopping in the parking lock control device which concerns on embodiment, (a) is a figure which shows the detection reference point of a resolver and the position of a claw of a parking pole, and (b) is a stop position. It is a figure which shows the stop position of the parking gear when the stop position is not adjusted, and (c) is the figure which shows the stop position of the parking gear when the stop position is adjusted. It is a flowchart which shows the flow of processing in EVCU of the parking lock control device which concerns on embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the figure, the same reference numerals are used for the same or corresponding parts. Further, in each figure, the same elements are designated by the same reference numerals and duplicate description will be omitted.

The parking lock control device 1 according to the embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a block diagram showing a configuration of a parking lock control device 1 according to an embodiment. FIG. 2 is a perspective view showing the configuration of the parking lock mechanism 20 controlled by the parking lock control device 1 according to the embodiment.

The parking lock control device 1 is mounted on an electric vehicle (EV (Electric Vehicle)) including an electric motor 10 as a drive source. The parking lock control device 1 controls the electric motor 10 during deceleration of the vehicle on a slope so that the parking pole 22 of the shift-by-wire (SBW (Shift By Wire)) type parking lock mechanism 20 meshes with the parking gear 21. Adjust the stop position of the parking gear 21.

The electric motor 10 functions as an electric motor and also as a generator. The electric motor 10 is, for example, a three-phase AC type motor generator. The electric motor 10 rotates a rotor (not shown) to generate power (torque) when the vehicle is accelerating, and outputs the power to an output shaft 10a connected to the rotor. When the vehicle is decelerated, the electric motor 10 generates electricity by utilizing the rotation of the drive wheels (not shown) transmitted via the speed reducer 2 and the output shaft 10a. The electric motor 10 is controlled by the inverter 11. The rotation angle of the rotor (output shaft 10a) of the electric motor 10 is detected by the resolver 12.

The power generated by the electric motor 10 is transmitted to the drive wheels via the speed reducer 2. The speed reducer 2 includes a drive gear 2a and a driven gear 2b that meshes with the drive gear 2a. The drive gear 2a is attached to the output shaft 10a of the electric motor 10. The driven gear 2b is connected to the drive wheels via, for example, a propeller shaft, a differential gear, a drive shaft, and the like.

The inverter 11 converts the DC power of the battery 13 into AC power, and supplies the AC power to the electric motor 10. Further, the inverter 11 converts the AC power generated by the electric motor 10 by regeneration into DC power. The electric power generated by this regeneration is stored in the battery 13. The inverter 11 is controlled by an EVCU (Electric Vehicle Control Unit) 14 described later.

The parking lock mechanism 20 includes a parking gear 21, a parking pole 22, a parking rod 23, a detent plate 24, and an SBW actuator 25.

The parking gear 21 is spline-fitted to the output shaft (corresponding to the power transmission shaft described in the claims) 10a of the electric motor 10. The parking gear 21 has teeth 21a arranged at regular intervals along the circumferential direction. A tooth groove 21b is formed between the teeth 21a and the teeth 21a adjacent to each other in the circumferential direction. In the present embodiment, the parking gear 21 is provided on the output shaft 10a of the electric motor 10, but the parking gear 21 may be provided at another location as long as it is directly connected to the electric motor 10, for example. , May be provided on the power transmission shaft connected to the driven gear 2b of the speed reducer 2.

The parking pole 22 is arranged in the vicinity of the parking gear 21. The parking pole 22 is provided on the parking gear 21 side so as to be swingable. A claw 22a that meshes with the tooth groove 21b of the parking gear 21 is provided on the surface of the parking pole 22 on the parking gear 21 side. When the parking pole 22 is swung toward the parking gear 21, the claw 22a meshes with an arbitrary tooth groove 21b of the parking gear 21.

The parking rod 23 is arranged on the back surface (the surface opposite to the surface on which the claw 22a is provided) of the parking pole 22. The parking rod 23 is provided so as to be movable in the axial direction in order to swing the parking pole 22. A tapered portion 23a is provided at the tip of the parking rod 23. When the parking rod 23 is advanced in the axial direction, the tapered portion 23a hits the back surface of the parking pole 22 and pushes the parking pole 22 toward the parking gear 21.

The detent plate 24 is connected to the parking rod 23. The detent plate 24 is provided so as to be swingable in order to advance and retreat the parking rod 23 in the axial direction. The detent plate 24 is swung by the SBW actuator 25.

A detent plate 24 is attached to the output shaft of the SBW actuator 25. The SBW actuator 25 swings the detent plate 24 by rotating. The SBW actuator 25 is controlled by the SBWCU (Shift By Wire Control Unit) 26.

The SBWCU 26 is a control unit that controls the parking lock mechanism 20. The SBWCU 26 drives and controls the SBW actuator 25 so that the parking pole 22 swings toward the parking gear 21 when the parking range is detected by the range switch 17 described later. The SBWCU 26 receives the detection information of the range switch 17 from the EVCU 14 via the CAN (Control Area Network) 40.

In the parking lock mechanism 20, when the parking range is selected by the driver, the SBW actuator 25 is rotated by the drive control by the SBWCU 26, so that the detent plate 24 is swung and the parking rod 23 advances in the axial direction. Will be done. The parking pole 22 is pushed toward the parking gear 21 by the tapered portion 23a of the advanced parking rod 23 to swing, and the claw 22a of the parking pole 22 meshes with the tooth groove 21b of the parking gear 21. As a result, the parking gear 21 is locked and the output shaft 10a of the electric motor 10 is fixed.

Since the parking gear 21 is provided on the output shaft 10a of the electric motor 10, it stops at a position (rotation angle) corresponding to the stop position (rotation angle) of the rotor (output shaft 10a) of the electric motor 10. Therefore, depending on the position of the tooth groove 21b of the parking gear 21, when the parking pole 22 is swung toward the parking gear 21, the claw 22a of the parking pole 22 causes the teeth 21a of the parking gear 21 (for example, the top of the teeth 21a). ), The claw 22a does not mesh with the tooth groove 21b. If they are not meshed, for example, when the vehicle stops on a slope and the driver releases the brake pedal depression without operating the side brake, the parking gear 21 rotates until the claw 22a meshes with the tooth groove 21b. To do. Along with this, the output shaft 10a, the drive gear 2a, the driven gear 2b, and the like of the electric motor 10 also rotate, and the vehicle may slide down on a slope. Therefore, in the parking lock control device 1, the parking gear 21 is controlled by the electric motor 10 so that the claw 22a of the parking pole 22 meshes with the tooth groove 21b of the parking gear 21 when the vehicle is decelerating on a slope. Adjust the stop position (rotation angle).

The control of the parking lock control device 1 with respect to the electric motor 10 is performed by the EVCU 14. The EVCU 14 is a control unit for an electric vehicle. The EVCU 14 drives and controls the electric motor 10 by controlling the inverter 11. The EVCU 14 includes a microprocessor that performs calculations, a ROM that stores programs for causing the microprocessor to execute each process, a RAM that stores various data such as calculation results, a backup RAM that holds the stored contents, and an input. It is configured to have an output I / F and the like.

The EVCU 14 is communicably connected to the SBWCU 26, the VDCU (Vehicle Dynamics Control Unit) 30, and the like, for example, via the CAN 40 in order to transmit and receive various information. The VDCU30 is a control unit that suppresses unstable behavior of the vehicle such as skidding. Various sensors such as a wheel speed sensor 31 and a G sensor 32 for each wheel are connected to the VDCU 30 in order to acquire information necessary for control. The wheel speed sensor 31 is a sensor that detects a wheel rotation state (wheel speed). The G sensor 32 is, for example, a sensor that detects acceleration in the front-rear direction, the lateral direction, and the like of the vehicle.

Various sensors such as a resolver 12, an accelerator pedal sensor 15, a brake pedal sensor 16, and a range switch 17 are connected to the EVCU 14. The accelerator pedal sensor 15 detects the opening degree of the accelerator pedal. The brake pedal sensor 16 is a sensor that detects the amount of depression of the brake pedal. The range switch 17 is connected so as to move in conjunction with the shift lever 18, and detects the selected position of the shift lever 18. With the shift lever 18, for example, the drive range, the parking range, the reverse range, and the neutral range can be selectively switched.

The EVCU 14 calculates the rotation angle of the rotor (output shaft 10a connected to the rotor) of the electric motor 10 by using the information detected by the resolver 12. Further, in the EVCU 14, the rotation speed (rotation speed) of the output shaft 10a is calculated by using the time series data of the rotation angle of the rotor of the electric motor 10. The program for calculating the rotation angle stored in the ROM is executed in the EVCU 14, and the microprocessor and the resolver 12 in which the function of calculating the rotation angle is realized correspond to the rotation angle acquisition means described in the claims.

Since the parking gear 21 is provided on the output shaft 10a of the electric motor 10 and rotates integrally with the output shaft 10a, the rotation angle of the rotor (output shaft 10a) of the electric motor 10 acquired by using the resolver 12 is parking. It corresponds to the rotation angle of the gear 21. Based on this rotation angle information, the EVCU 14 can acquire each tooth groove 21b of the parking gear 21 (for example, the center position in the circumferential direction of the tooth groove 21b), and the claw 22a of the parking pole 22 swung toward the parking gear 21 side. The position of the tooth groove 21b (relative position) and the position of the tooth groove 21b with respect to the detection reference point (zero point) of the resolver 12 can be acquired. Therefore, the program for acquiring the tooth groove position stored in the ROM is executed in the EVCU 14, and the microprocessor and the resolver 12 in which the function of acquiring the tooth groove position is realized describe the tooth groove position acquisition in the claims. Corresponds to means.

The EVCU 14 sets a target torque based on, for example, the driving state of the vehicle (for example, the vehicle speed, the opening degree of the accelerator pedal, the amount of depression of the brake pedal), and transmits this target torque to the inverter 11. The inverter 11 drives and controls the electric motor 10 based on this target torque. In the drive control for the electric motor 10, the actual rotation angle and the actual rotation speed of the rotor of the electric motor 10 detected by the resolver 12 are used.

In particular, the EVCU 14 includes a control intervention determination unit 14a, an angular velocity calculation unit 14b, an angular acceleration calculation unit 14c, and a stop position in order to adjust the stop position of the parking gear 21 when the vehicle decelerates and stops on a slope. It has a meshing position determining unit 14d and a parking gear stop position controlling unit 14e. In the EVCU 14, each function of the control intervention determination unit 14a, the angular velocity calculation unit 14b, the angular acceleration calculation unit 14c, and the stop meshing position determination unit 14d is realized by executing the program stored in the ROM by the microprocessor. To.

The control intervention determination unit 14a determines whether or not the brake pedal is depressed (whether or not the vehicle is decelerating) by using the detection information of the brake pedal sensor 16. When the control intervention determination unit 14a determines that the brake pedal is not depressed, the functions of the units 14b to 14e other than the control intervention determination unit 14a are not executed.

The control intervention determination unit 14a determines whether or not the slope of the road surface is equal to or greater than a predetermined gradient. As a method of acquiring the slope of the road surface, for example, the acceleration information in the front-rear direction detected by the G sensor 32 is received from the VDCU30 via the CAN 40, and the control intervention determination unit 14a uses the acceleration in the front-rear direction to obtain the slope of the road surface ( There is a method to estimate the tilt angle). The predetermined slope is a threshold value for determining that the road is a slope (for example, a slope having a slope on which the vehicle may slide down). When the control intervention determination unit 14a determines that the slope of the road surface is less than a predetermined gradient, each function of each unit 14b to 14e other than the control intervention determination unit 14a is not executed.

The control intervention determination unit 14a determines whether or not the deceleration of the vehicle is equal to or less than a predetermined deceleration. As a method of acquiring the deceleration of the vehicle, for example, the information of the wheel speed detected by the wheel speed sensor 31 is received from the VDCU30 via the CAN 40, and the deceleration of the vehicle is calculated using the time series data of the wheel speed. There is a way. The predetermined deceleration is a threshold value for determining sudden deceleration (particularly, sudden braking) in response to a sudden braking operation by the driver. When the control intervention determination unit 14a determines that the deceleration of the vehicle is larger than the predetermined deceleration, the functions of the units 14b to 14e other than the control intervention determination unit 14a are not executed. The vehicle speed is calculated from the rotation speed of the output shaft 10a acquired by using the resolver 12, and the vehicle speed is time-differentiated using the calculated time-series data of the vehicle speed to obtain the deceleration of the vehicle. May be good.

When the control intervention determination unit 14a determines that the brake pedal is depressed, the slope of the road surface is determined to be equal to or higher than the predetermined gradient, and the deceleration of the vehicle is determined to be equal to or lower than the predetermined deceleration, the parking gear 21 is stopped. In order to adjust the position, each function of each part 14b to 14e is performed.

The angular velocity calculation unit 14b differentiates the rotation angle of the output shaft 10a with respect to the first order using the time-series data of the rotation angle of the output shaft 10a (parking gear 21) of the electric motor 10 acquired by using the resolver 12, and the angular velocity. To get. The angular velocity calculation unit 14b and the resolver 12 correspond to the angular velocity acquisition means described in the claims.

The angular acceleration calculation unit 14c uses the time-series data of the rotation angle of the output shaft 10a (parking gear 21) of the electric motor 10 acquired by using the resolver 12 to differentiate the rotation angle of the output shaft 10a into the second-order time. Acquires angular acceleration (angular deceleration). The angular acceleration calculation unit 14c may obtain the angular acceleration by first-order time differentiation using the time-series data of the angular velocity calculated by the angular velocity calculation unit 14b. The angular acceleration calculation unit 14c and the resolver 12 correspond to the angular acceleration acquisition means described in the claims.

The meshing position determining unit 14d at the time of stopping uses the position of the tooth groove 21b of the parking gear 21 acquired at an arbitrary timing and the parking gear 21 (output shaft 10a of the electric motor 10) when the position of the tooth groove 21b is acquired. ), The angular velocity and the angular acceleration of) are used to determine the meshing position of the parking gear 21 when stopped. The position of the tooth groove 21b of the parking gear 21 is, for example, the relative position of the tooth groove 21b with respect to the position of the claw 22a of the parking pole 22. The stopped meshing position of the parking gear 21 is the position of the tooth groove 21b of the parking gear 21 in which the claw 22a of the parking pole 22 meshes when the rotation of the electric motor 10 (and by extension, the vehicle) stops. The position of these tooth grooves 21b is represented by a rotation angle, and may be represented by, for example, the angle of the tooth groove 21b with respect to the detection reference point of the resolver 12 (for example, the angle of the center position in the circumferential direction of the tooth groove 21b). Alternatively, it may be represented by the angle of the tooth groove 21b with respect to the position of the claw 22a of the parking pole 22 swung toward the parking gear 21 side. It should be noted that the stop meshing position determining unit 14d corresponds to the stop meshing position determining means described in the claims.

With reference to FIG. 3, an example of a method of determining the stop meshing position in the stop mesh position determination unit 14d will be described. 3A and 3B are explanatory views of a method of determining the meshing position at the time of stopping, in which FIG. 3A shows the detection reference point of the resolver 12 and the position of the claw 22a of the parking pole 22, and FIG. 3B is a diagram for adjusting the stop position. It is a figure which shows the stop position of the parking gear 21 when it is not, and (c) is the figure which shows the stop position of the parking gear 21 when the stop position is adjusted.

As shown in FIG. 3A, the detection reference point (zero point) of the resolver 12 is set to the position indicated by the symbol RP. Further, the center position of the claw 22a of the parking pole 22 swung toward the parking gear 21 side is set to the position indicated by the symbol PP. The center position PP of the claw 22a is an angle θ _P with respect to the detection reference point RP of the resolver 12. In the example shown in FIG. 3, the number of teeth 21a and tooth grooves 21b of the parking gear 21 is 18, and the angle Δθ between the adjacent tooth grooves 21b and 21b (the angle between the adjacent teeth 21a and 21a) is 20. °. Each of these values is stored in a ROM or the like in the EVCU 14.

In FIG. 3A, in the case of the position of the parking gear 21 shown by the solid line, the position of the claw 22a of the parking pole 22 swung toward the parking gear 21 and the position of the tooth groove 21b of the parking gear 21 coincide with each other. The position θ ₀ of the tooth groove 21b of the parking gear 21 is 0 °. Further, in the case of the position of the parking gear 21 shown by the broken line in FIG. 3A, the position of the tooth groove 21b of the parking gear 21 is equal to the position of the claw 22a of the parking pole 22 swung toward the parking gear 21 side. The position θ ₀ of the tooth groove 21b of the parking gear 21 is deviated from the center position PP of the claw 22a of the parking pole 22. Using the position θ ₀ of the tooth groove 21b of the parking gear 21 and the angular velocity ω and the angular acceleration (angular deceleration) α when the position θ _{0 of the} tooth groove 21b is acquired, the meshing position θ _st at the time of stopping is set. It is determined.

Assuming that the rotation of the electric motor 10 is stopped by the normal control and the time until the rotation of the electric motor 10 is stopped by the normal control is t, the angular velocity ω and the angular acceleration are obtained according to the following (Equation 1). Time t is calculated using α.
t = ω / | α | ... (Equation 1)

Assuming that the total rotation angle until the rotation of the electric motor 10 is stopped is θ _t , the total rotation angle θ _t is calculated by using the angular velocity ω and the time t according to the following (Equation 2).
θ _t = ω × t ... (Equation 2)

Since the parking gear 21 is provided on the output shaft 10a of the electric motor 10, the parking gear 21 rotates by a total rotation angle θ _t from the position θ ₀ (initial position) of the tooth groove 21b and stops. Assuming that the rotation angle of the parking gear 21 is θ _g , the rotation angle θ _g is calculated by using the position θ ₀ of the tooth groove 21 b and the total rotation angle θ _{t according} to the following (Equation 3). This rotation angle θ _g is the tooth of the parking gear 21 when the rotation of the electric motor 10 is stopped when the electric motor 10 is stopped by normal control (when the control for adjusting the stop position of the parking gear 21 is not performed). It corresponds to the position of the groove 21b.
θ _g = θ ₀ + θ _t ... (Equation 3)

When the electric motor 10 is stopped by normal control, for example, if the parking gear 21 is stopped at the position shown in FIG. 3B, the position GP of the tooth groove 21a of the parking gear 21 is the claw 22a of the parking pole 22. The angle θ _s deviates from the position PP of. In this case, if the parking pole 22 is swung toward the parking gear 21 after the electric motor 10 is stopped, the claw 22a of the parking pole 22 does not mesh with the tooth groove 21a of the parking gear 21.

Therefore, as shown in FIG. 3C, when the electric motor 10 is stopped, the position GP of the tooth groove 21a of the immediately preceding parking gear 21 (when the electric motor 10 is stopped by normal control, the parking pole 22 The rotation angle θ _g calculated so that the position of the tooth groove 21a closest to the position PP of the claw 22a among the tooth grooves 21a passing through the position PP of the claw 22a coincides with the position PP of the claw 22a of the parking pole 22). The stop position of the parking gear 21 is obtained from. The stop position of the parking gear 21 is the meshing position θ _st when stopped. For example, when the rotation angle θ _g is an integral multiple of the angle Δθ between the tooth grooves 21b and 21b, the tooth groove 21a of the parking gear 21 does not shift with respect to the position of the claw 22a of the parking pole 22, so that the rotation angle θ _g is set. The meshing position when stopped is θ _st . On the other hand, when the rotation angle θ _g is not an integral multiple of the angle Δθ between the tooth grooves 21b and 21b, the tooth groove 21a of the parking gear 21 is displaced with respect to the position of the claw 22a of the parking pole 22 (for example, FIG. 3B. ), The angle obtained by subtracting the deviation angle from the rotation angle θ _g is defined as the stop meshing position θ _st . In this way, the meshing position θ _st when stopped is determined.

When stopped, the meshing position determining unit 14d uses the position θ ₀ , the angular velocity ω, and the angular acceleration α of the tooth groove 21b acquired at each predetermined time until immediately before the rotation of the electric motor 10 stops. The meshing position θ _st is determined. Therefore, the meshing position θ _st when stopped is updated at predetermined time _intervals . When the angular velocity ω becomes equal to or lower than a predetermined angular velocity (immediately before the rotation of the electric motor 10 stops), the position θ ₀ of the tooth groove 21b at that time and the angular velocity ω in the stop meshing position determining unit 14d. , The angular acceleration α may be used to determine the meshing position θ _st when stopped.

In the case of the above-described determination method, the meshing position at the time of stop is determined by using the position GP of the tooth groove 21a of the parking gear 21 immediately before the stop position by normal control. Therefore, when the electric motor 10 is stopped at this meshing position at the time of stop. The rotation angle of the electric motor 10 until it is stopped is smaller than that of stopping the electric motor 10 by normal control, and the braking distance of the vehicle is not extended. The meshing position at the time of stopping may be determined by using the position of the tooth groove 21a of the parking gear 21 immediately after the stop position by normal control.

The parking gear stop position control unit 14e drives and controls the electric motor 10 by controlling the inverter 11 so that the parking gear 21 stops at the meshing position when stopped. Specifically, the parking gear stop position control unit 14e is determined by the stop meshing position determination unit 14d, for example, when the angular velocity ω becomes equal to or lower than a predetermined angular velocity (immediately before the rotation of the electric motor 10 stops). The target stop rotation angle of the rotor of the electric motor 10 is set based on the stopped meshing position, and this target stop rotation angle is transmitted to the inverter 11. In the inverter 11, the electric motor 10 is controlled so that the rotor of the electric motor 10 stops at the target stop rotation angle. The parking gear stop control unit 14e and the inverter 11 correspond to the control means described in the claims.

The operation of the parking lock control device 1 will be described with reference to FIGS. 1 and 2. In particular, the processing of the parking lock control device 1 in the EVCU 14 will be described with reference to the flowchart of FIG. FIG. 4 is a flowchart showing the flow of processing in the EVCU 14 of the parking lock control device 1 according to the embodiment. In the parking lock control device 1, the following processes are repeatedly performed at predetermined time intervals.

The EVCU 14 determines whether or not the brake pedal is depressed (S10). If it is determined in the determination of S10 that the brake pedal is not depressed, the EVCU 14 temporarily exits the process.

When it is determined in the determination of S10 that the brake pedal is depressed (the vehicle is decelerating), the EVCU 14 determines whether or not the slope of the road surface is equal to or greater than a predetermined gradient (S12). If it is determined in the determination of S12 that the slope of the road surface is less than a predetermined gradient, the EVCU 14 temporarily exits the process.

When it is determined in the determination of S12 that the slope of the road surface is equal to or greater than the predetermined gradient (in the case of a slope), the EVCU 14 determines whether or not the deceleration of the vehicle is equal to or less than the predetermined deceleration (S14). When it is determined in the determination of S14 that the deceleration of the vehicle is larger than the predetermined deceleration (in the case of sudden braking), the EVCU 14 temporarily exits the process.

When the deceleration of the vehicle is determined to be less than or equal to the predetermined deceleration in the determination of S14 (when the braking is not sudden), the EVCU 14 determines the position (rotation) of the rotor (output shaft 10a) of the electric motor 10 from the detection information of the resolver 12. The angle) is acquired, and the position of the tooth groove 21b of the parking gear 21 is acquired from the position of this rotor (S16).

The EVCU 14 calculates the angular velocity using the time-series data of the rotation angle of the rotor (output shaft 10a) of the electric motor 10 acquired from the detection information of the resolver 12 (S18). Further, the EVCU 14 calculates the angular acceleration using the time-series data of the rotation angle of the rotor (output shaft 10a) of the electric motor 10 acquired from the detection information of the resolver 12 (S20).

The EVCU 14 determines the stop meshing position of the parking gear 21 by using the position of the tooth groove 21b of the parking gear 21 and the angular velocity and the angular acceleration when the position of the tooth groove 21b is acquired (S22).

The EVCU 14 controls the inverter 11 so that the parking gear 21 stops at the meshing position when stopped (S24). In response to this control, the inverter 11 drives and controls the electric motor 10. In the drive-controlled electric motor 10, the rotor stops at a predetermined position (rotation angle). When the electric motor 10 stops at this position, the parking gear 21 (particularly, the tooth groove 21b) is stopped at the meshing position when stopped. Further, when the rotation of the electric motor 10 is stopped, the vehicle stops on a slope.

When the parking range is selected by the driver's operation of the shift lever after the vehicle is stopped, the range switch 17 detects the parking range. When the parking range is detected by the range switch 17, the SBWCU 26 drives and controls the SBW actuator 25. By rotating the SBW actuator 25 by this drive control, the detent plate 24 is swung and the parking rod 23 is advanced in the axial direction. The advanced parking rod 23 swings the parking pole 22 toward the parking gear 21, and the claw 22a of the parking pole 22 swings toward the parking gear 21.

Since the stop position of the tooth groove 21b of the parking gear 21 is adjusted by the drive control with respect to the electric motor 10, the claw 22a of the parking pole 22 swinging toward the parking gear 21 meshes with the tooth groove 21b of the parking gear 21. As a result, the parking gear 21 is locked and the output shaft 10a of the electric motor 10 is fixed.

For example, even when the driver depresses the brake pedal without operating the side brake, the claw 22a of the parking pole 22 meshes with the tooth groove 21b of the parking gear 21, so that the parking gear 21 (output shaft 10a) is engaged. ) Does not rotate, and the drive wheels connected to the output shaft 10a also do not rotate. Therefore, the vehicle does not slide down on a slope.

In addition, in order to adjust the stop position of the parking gear 21, the electric motor 10 which is the drive source of the electric vehicle and the inverter 11 which drives and controls the electric motor 10 are used, so that it is necessary to separately provide the adjusting means. Absent. Further, since the resolver 12 that detects the rotation angle of the rotor of the electric motor 10 and the like is used to acquire the position of the tooth groove 21b of the parking gear 21, it is not necessary to separately provide a sensor. Further, since the resolver 12 is used to acquire the angular velocity and the angular acceleration of the parking gear 21 (output shaft 10a of the electric motor 10), it is not necessary to separately provide a sensor.

According to the parking lock control device 1 according to the embodiment, the parking range is suppressed while suppressing the cost by adjusting the stop position of the parking gear 21 by using the electric motor 10, the inverter 11, and the resolver 12 provided in the electric vehicle. It is possible to prevent the vehicle from slipping down after the is selected.

According to the parking lock control device 1 according to the embodiment, the electric motor 10 is used by using the position (initial position) of the tooth groove 21b of the parking gear 21 and the angular velocity and the angular velocity when the position of the tooth groove 21b is acquired. Since the time required until the vehicle stops (until the vehicle stops) and the total rotation angle can be accurately obtained, the tooth groove 21b of the parking gear 21 when the rotation of the electric motor 10 is stopped by normal control based on these values. The position (rotation angle) can be estimated accurately, and the meshing position at the time of stopping can be accurately determined. In particular, according to the parking lock control device 1 according to the embodiment, the meshing position immediately before the position of the tooth groove 21b of the parking gear 21 when the rotation of the electric motor 10 is stopped by this normal control is determined as the meshing position at the time of stopping. By doing so, the braking distance of the vehicle is not extended as compared with stopping the electric motor 10 by normal control.

According to the parking lock control device 1 according to the embodiment, control is performed to adjust the stop position of the parking gear 21 when the slope of the road surface is equal to or higher than a predetermined slope, so that the vehicle slides on a slope having a slope equal to or higher than the predetermined slope. It is possible to prevent the drop. When the road surface is flat, even if the claw 22a of the parking pole 22 does not normally mesh with the tooth groove 21b of the parking gear 21, the driver does not operate the side brake and the brake pedal is released. However, the vehicle does not slide down.

According to the parking lock control device 1 according to the embodiment, control for adjusting the stop position of the parking gear 21 (control of the stop position with respect to the electric motor 10) is performed only when the deceleration is equal to or less than a predetermined deceleration, and the deceleration is performed. However, since this control is not performed during sudden braking exceeding a predetermined deceleration, the vehicle can be stopped in response to the driver's sudden braking operation during sudden braking.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be modified in various ways. For example, although it is applied to an electric vehicle having only an electric motor 10 as a drive source, it can also be applied to a hybrid vehicle having an electric motor and an engine as a drive source. Applicable hybrid vehicles are, for example, not provided with a clutch or automatic transmission in the power transmission path between the electric motor and the drive wheels, but are provided with parking gears on the power transmission shaft of this power transmission path. This is a vehicle in which the power transmission path and the engine are separated during deceleration.

In the above embodiment, the resolver 12 is used as the rotation angle detecting means of the electric motor 10, but another rotation angle detecting means such as a sensor using an encoder may be used.

In the above embodiment, the resolver 12 of the electric motor 10 is used as the position acquisition means of the tooth groove 21b of the parking gear 21, but an electromagnetic pickup type sensor, a sensor using an MR element, a sensor using a Hall element, etc. Another configuration may be provided in which the tooth groove position acquisition means is separately provided.

In the above embodiment, the application is applied to a vehicle provided with a shift-by-wire type parking lock mechanism 20, but it can also be applied to a vehicle provided with a mechanical parking lock mechanism.

In the above embodiment, the angular velocity and angular acceleration of the parking gear 21 (output shaft 10a of the electric motor 10) are acquired by using the time-series data of the rotation angle obtained from the detection information of the resolver 12, but another method is used. The angular velocity and the angular acceleration may be acquired, for example, the angular velocity may be acquired from the vehicle speed acquired by using a wheel speed sensor or the like, or from the time series data of the vehicle speed acquired by using a wheel speed sensor or the like. The angular acceleration may be acquired. Further, when determining the meshing position when stopped, the vehicle speed or acceleration (deceleration) of the vehicle may be used instead of the angular velocity or angular acceleration.

1 Parking lock controller 10 Electric motor 10a Output shaft 11 Inverter 12 Resolver 14 EVCU
14a Control intervention judgment unit 14b Angular velocity calculation unit 14c Angular acceleration calculation unit 14d Engagement position determination unit when stopped 14e Parking gear stop position control unit 17 Range switch 18 Shift lever 20 Parking lock mechanism 21 Parking gear 21a Tooth 21b Tooth groove 22 Parking pole 22a Claw 23 Parking rod 24 Detent plate 25 SBW actuator 26 SBWCU

Claims (5)

A parking lock control device mounted on a vehicle equipped with an electric motor as a drive source.
A parking gear provided on a power transmission shaft that transmits power generated by the electric motor, and
A parking pole having a claw and locking the parking gear by engaging the claw with the tooth groove between the teeth of the parking gear.
During deceleration of the vehicle, the position of the tooth groove of the parking gear when the rotation of the electric motor is stopped due to the deceleration is estimated, and based on the estimated position of the tooth groove of the parking gear, the electric motor When the rotation is stopped, the claws of the parking pole mesh with the tooth grooves of the parking gear, and the stop meshing position determining means for determining the stop meshing position of the parking gear.
A control means for controlling the electric motor so that the parking gear stops at the stop meshing position determined by the stop meshing position determining means.
Equipped with a,
The parking lock control device is characterized in that the stop meshing position determining means determines a meshing position in front of the estimated tooth groove position of the parking gear as the stop meshing position . A parking lock control device mounted on a vehicle equipped with an electric motor as a drive source.
A parking gear provided on a power transmission shaft that transmits power generated by the electric motor, and
A parking pole having a claw and locking the parking gear by engaging the claw with the tooth groove between the teeth of the parking gear.
During deceleration of the vehicle, the position of the tooth groove of the parking gear when the rotation of the electric motor is stopped due to the deceleration is estimated, and based on the estimated position of the tooth groove of the parking gear, the electric motor When the rotation is stopped, the claws of the parking pole mesh with the tooth grooves of the parking gear, and the stop meshing position determining means for determining the stop meshing position of the parking gear.
A control means for controlling the electric motor so that the parking gear stops at the stop meshing position determined by the stop meshing position determining means.
It is equipped with a slope acquisition means for acquiring the slope of the road surface.
The control means controls the electric motor so that the parking gear stops at the meshing position at the time of stopping when the gradient acquired by the gradient acquisition means is equal to or higher than a predetermined gradient. Control device. A parking lock control device mounted on a vehicle equipped with an electric motor as a drive source.
A parking gear provided on a power transmission shaft that transmits power generated by the electric motor, and
A parking pole having a claw and locking the parking gear by engaging the claw with the tooth groove between the teeth of the parking gear.
During deceleration of the vehicle, the position of the tooth groove of the parking gear when the rotation of the electric motor is stopped due to the deceleration is estimated, and based on the estimated position of the tooth groove of the parking gear, the electric motor When the rotation is stopped, the claws of the parking pole mesh with the tooth grooves of the parking gear, and the stop meshing position determining means for determining the stop meshing position of the parking gear.
A control means for controlling the electric motor so that the parking gear stops at the stop meshing position determined by the stop meshing position determining means.
Equipped with a deceleration acquisition means to acquire the deceleration of the vehicle,
The control means is characterized in that when the deceleration acquired by the deceleration acquisition means is equal to or less than a predetermined deceleration, the electric motor is controlled so that the parking gear stops at the meshing position at the time of stop. Parking lock control device. Tooth groove position acquisition means for acquiring the position of the tooth groove of the parking gear, and
An angular velocity acquisition means for acquiring the angular velocity of the parking gear, and
An angular acceleration acquisition means for acquiring the angular acceleration of the parking gear, and
With
The stop meshing position determining means acquires the position of the tooth groove acquired by the tooth groove position acquisition means, the angular velocity acquired by the angular velocity acquisition means when the position of the tooth groove is acquired, and the angular acceleration. The parking lock control device according to any one of claims 1 to 3 , wherein the meshing position at the time of stopping is determined by using the angular acceleration acquired by the means. The invention is characterized in that the tooth groove position acquisition means acquires the position of the tooth groove of the parking gear by using the rotation angle acquired by the rotation angle acquisition means for acquiring the rotation angle of the rotor of the electric motor. 4. The parking lock control device according to 4.

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