JP2003148599A - Electric range switching device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rotate and drive a manual shaft with a simple configuration and without overshooting to an angle corresponding to a required range. SOLUTION: The maximum voltage is applied to a motor until the manual shaft rotates only a prescribed rate RATE1 of a required rotating angle A corresponding to the switch of the required range after the required range is switched. The power supply is stopped to the motor when the manual shaft rotates only the prescribed rate RATE1 of the required rotating angle A. The stop of the power supply is continued for only the time Tb of the prescribed rate RATE2 of the time Ta required for rotating only the prescribed rate RATE1 of the required rotating angle A from the control starting. Meanwhile, inertia torque is discharged. The motor is controlled based on a correction value and a feedback control value corresponding to the remaining inertia torque after continuing the stop of the power supply for only the time Tb.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric range switching device for an automatic transmission having a structure in which a manual shaft is driven by a motor to drive a manual valve.

[0002]

2. Description of the Related Art Conventionally, when a motor is operated on the basis of a range switching request and the manual shaft rotates to a position near an angle corresponding to a target range, a reverse voltage is applied to the motor to apply a braking force to the motor. There is known an electric range switching device for an automatic transmission, which is configured to be generated and feedback-controlled so that the angle of the manual shaft becomes an angle corresponding to a target range and is stopped (see Japanese Patent Laid-Open No. 7-305770). .

[0003]

However, in the above configuration, since the start timing of the braking control and the request for the gain during braking change depending on the power supply voltage and the environmental temperature at that time, the timing that can converge to the target with good response. There is a problem that it is difficult to adapt the gain. The present invention has been made in view of the above problems, and provides an electric range switching device for an automatic transmission, which can automatically adjust the control switching timing with respect to changes in environmental conditions and can significantly reduce the number of control specification conforming steps. The purpose is to provide.

[0004]

Therefore, according to the invention of claim 1, the manual valve is driven by the manual shaft which is rotationally driven by the motor.
In an electric range switching device of an automatic transmission that drives and controls a motor so that an angle of a manual shaft becomes an angle corresponding to a required range, after starting power supply to the motor to cope with a change in the required range, The power supply to the motor is stopped when the predetermined ratio of the angle change width of the manual shaft corresponding to the change of the required range is reached, and then the predetermined ratio of the time required until the predetermined ratio of the angle change width is reached. The power supply is stopped for a period of time, and after the power supply is stopped, the motor is feedback-controlled so that the actual angle of the manual shaft becomes the angle corresponding to the required range.

According to the above construction, when the required range is changed, power supply to the motor is started to rotate the manual shaft, but when the manual shaft is rotated by a predetermined ratio of the angle required to rotate, the motor is supplied to the motor. Power supply is temporarily stopped, and the power supply stop state is continued for a predetermined percentage of the time required from the start of power supply to the stop, and the inertia shaft of the manual shaft is released during this stop period to supply power. Power is supplied again after the stop time has elapsed, but at this time, feedback control is performed to match the angle of the manual shaft with the target.

According to the second aspect of the invention, the control signal of the motor is kept constant from the start of the power supply to the motor to the stop of the power supply. According to the above configuration, the feedback control is not performed from the start of power supply until the rotation of the motor by the predetermined ratio of the required rotation angle, and the motor is driven by the constant control signal.

According to the third aspect of the invention, in the feedback control after the power supply stop time has elapsed, the feedback control amount according to the deviation between the actual manual shaft angle and the target angle corresponding to the required range. ,
The motor control signal is determined from the correction amount according to the inertia torque of the manual shaft. According to the above configuration, the feedback control is performed after the power supply stop time has elapsed, but the feedback control amount and the correction amount corresponding to the inertia torque of the manual shaft are obtained, and the feedback control amount and the inertia torque are determined. The motor is controlled based on the correction amount.

According to a fourth aspect of the present invention, the correction amount according to the inertia torque is based on the difference between the inertia torque at the time when the power supply is stopped and the inertia torque released during the power supply stop. The configuration was decided. According to the above configuration, the correction amount is determined according to the inertia torque remaining due to the release of the inertia torque during the power supply stop time.

According to the fifth aspect of the invention, the feedback control is terminated when it is continuously determined that the actual angle of the manual shaft is within a predetermined angle range including the angle corresponding to the required range. did. According to the above configuration, the angle of the manual shaft is within the predetermined angle range including the angle corresponding to the required range by the feedback control, and when the state of being within the predetermined angle range continues, the angle becomes suitable for the required range. Judge and terminate the feedback control.

[0010]

According to the first aspect of the present invention, the control switching timing is determined based on the degree of progress of the angle change of the manual shaft. Therefore, the switching timing is automatically changed according to the change of the shift speed due to the change of the environmental condition. The inertia torque is released by stopping the motor drive when the angle change has progressed to a certain degree, so that the amount of brake control is suppressed and the occurrence of overshoot is prevented. There is an effect that the convergence to the target angle can be improved.

According to the second aspect of the invention, the motor is controlled by a constant control signal until the predetermined ratio of the required angle change width is reached, so that the shift speed during that time is maintained at the maximum and the shift is performed. The time can be shortened, and since the feedback control is limited to the braking control when the angle of the manual shaft becomes close to the target, there is an effect that the number of man-hours for gain adjustment can be reduced.

According to the third aspect of the present invention, different braking demands are feedforward controlled depending on the inertia torque of the manual shaft, so that the braking can be operated with good response and the convergence to the target can be enhanced. is there. According to the invention described in claim 4, it is possible to accurately estimate the amount of the inertia torque remaining due to the release of the inertia torque within the power supply stop time, improve the accuracy of the braking control during the feedback control, and converge to the target angle. There is an effect that can improve.

According to the invention described in claim 5, there is an effect that it is possible to make an accurate judgment without erroneously judging the end of the feedback control.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a system configuration diagram of an electric range switching device for an automatic transmission according to an embodiment. In FIG. 1, a motor 2 as an actuator of an electric range switching device is attached to an automatic transmission 1 for a vehicle.

A deceleration mechanism 3 is provided on the output shaft of the motor 2, and the manual shaft 4 is rotationally driven via the deceleration mechanism 3. A detent mechanism 5 for positioning the manual shaft 4 at angles corresponding to a plurality of ranges is attached to the manual shaft 4. As shown in FIG. 2, the detent mechanism 5 includes a detent lever 5A and a detent lever 5A that are fixed to the manual shaft 4 and rotate integrally.
A detent spring 5B that supports a roller that engages with a recess formed corresponding to each range on the periphery of the manual shaft, and that biases the roller toward the notch. Position at an angle corresponding to any of the R range, N range, D range, 2 range, and 1 range.

The rotational movement of the manual shaft 4 is
By engaging the detent lever 5A with the manual valve 6 (spool valve), the movement of the manual valve 6 is converted into the axial movement of the manual valve 6, and the manual valve 6 is displaced in the axial direction of the valve body 7, thereby opening and closing the hydraulic port. The frictional engagement elements are switched to control the release / fastening of the friction engagement elements for setting each shift range.

A cam 9 is attached to the other end of the rod 8 whose one end is attached to the detent lever 5A.
The parking pole 10 supported so as to be swingable is driven to swing by the sliding contact with the cam 9, and at the P range position, the claw 10a of the parking pole 10 meshes with the recess 11a of the parking gear 11 to cause the parking gear 11 to move.
Is fixed.

Further, the manual shaft 4 is provided with a potentiometer 21 for detecting the angle of the manual shaft 4 (detent lever 5A), and an inhibitor switch 22 for detecting which one of the ranges is selected. To be In addition, the A / T select lever operated by the driver allows the P, R, N,
A range select switch 23 is provided to detect which of D, 2, and 1 ranges is selected.

Signals from the potentiometer 21, the inhibitor switch 22 and the range select switch 23 are sent to an A / T control unit (A / T C / U).
24 is input. The A / T control unit 2
4 determines the range selected by the driver based on the signal from the range select switch 23, and sets the manual shaft 4 (manual valve) at a position corresponding to the range.
The motor 2 is controlled based on the actual angle detected by the potentiometer 21 in order to drive the motor 2.

Hereinafter, the A / T control unit 2 will be described.
4 will be described in detail according to the flowcharts of FIGS. 4 to 6 with reference to the time chart of FIG. The flowchart of FIG. 4 shows a main routine of motor control, and in step S1, information such as the actual angle of the manual shaft 4 detected by the potentiometer 21 is input.

In the next step S2, the start / end of control is determined. Start of control in step S2
Details of the end determination are shown in the flowchart of FIG.
In the flowchart of FIG. 5, in step S201, the target angle corresponding to the range and the potentiometer 2 are set.
The deviation Err (Err = target angle−actual angle) from the actual angle detected in 1 is calculated.
It is determined whether or not the absolute value of the deviation Err exceeds a predetermined value HYS1.

The absolute value of the deviation Err is a predetermined value HYS1.
If it exceeds, the process proceeds to step S203 to determine the start of motor control (see FIG. 7). Step S2
After the start of motor control is determined in step 03, step S20
When it is determined in step 4 that the absolute value of the deviation Err is smaller than the predetermined value HYS2 for two or more times in succession, the process proceeds to step S205 to determine the end of motor control (see FIG. 7). ).

When it is determined in step S203 that the motor control is started, the control from step S3A is executed. In step S3A, the shift progress state is determined, and in step S3B, the control method is selected based on the shift progress state determination result. Step S3A,
Details of the processing in 3B are shown in the flowchart of FIG.

In the flowchart of FIG. 6, in step S301, the rotation angle S of the manual shaft 4 is
It is calculated as the absolute value of the deviation between the angle at the start of control and the angle at the present time. In step S302, a timer TIMER1 for measuring the elapsed time from the start of motor control (start of power supply) is counted up.

In step S303, the rotation angle S up to the present is smaller than the predetermined ratio RATE1 (0.632 in this embodiment) of the required rotation angle A (see FIG. 3) that requires the manual shaft 4 to be rotated when the range is switched. It is determined whether it is small. Then, the required rotation angle A × RAT
When the rotation angle S up to now is smaller than E1, the process proceeds to step S304.

In step S304, the control duty signal for switching control of the power supply to the motor 2 is set to 100% ON duty corresponding to the shift switching direction, and the direction of the motor 2 corresponding to the shift switching direction is set. Apply maximum voltage. In this embodiment, 100% ON duty is output in step S304, but the present invention is not limited to 100% ON duty, and an arbitrary fixed value may be used.

In step S305, the above 100% is turned on.
With the control by the duty, it is determined whether or not the angle A × RATE1 = the rotation angle S up to the present time is reached, and A × RATE is determined.
Until 1 = S, 100% ON duty is continuously output, and rotation is performed up to S = A × RATE1 at maximum acceleration. When A × RATE1 = S, step S306
Then, the control duty signal is set to 0% ON duty to stop the power supply to the motor 2 to release the inertia torque of the manual shaft 4.

In step S307, the timer TIMER2 for measuring the motor stop time is counted up. In step S308, the output period of 100% ON duty measured by the timer TIMER1, that is,
A predetermined ratio RATE2 of the time Ta required from the start of control until A × RATE1 = S (0.632 in this embodiment)
It is determined whether the motor stop time TIMER2 is longer than the time Tb (Tb = Ta × RATE2).

While Tb ≧ TIMER2, the motor 2 is continuously stopped as it is, but when Tb <TIMER2, the process proceeds to step S309 and the timer TIMER is set.
1, after resetting TIMER2, step S310
Brake control. Specifically, the brake control includes feedforward control (FF control) in step S4 of the flowchart of FIG. 4 and feedback control (FB control) in step S5.

In the feed forward control (FF control), the residual inertia torque β at the start of the brake control is
A correction amount corresponding to is calculated. Here, the inertia torque of the manual shaft 4 has a load torque T (θ) according to the angular position θ, a motor terminal current I, and a torque constant K.
f, the inertia torque is calculated as Kf × IT (θ), and the load torque T (θ) is calculated in advance from FIG.
The map can be stored in a map as shown in FIG. 7 and the inertia torque α at the time when the power supply is stopped is calculated based on the above equation.

However, the torque detected by the torque sensor may be used as the load torque T (θ).
Then, the inertia torque α at the time when the power supply was stopped
The residual inertia torque β obtained by subtracting the emission inertia torque during the power supply stop period from is calculated as β = α × (1-0.632).

The residual inertia torque β is set to a resistance value R
When converted into a voltage Vβ using, Vβ = (β / Kf) × R, and the correction amount of the control signal is applied so that the voltage Vβ is applied to the motor 2 in the opposite direction to the direction corresponding to the shift switching. To decide. In the feed forward control (FF control), the residual inertia torque β
In addition to the correction amount according to the above, it is possible to add the correction amount due to the power supply voltage or the temperature.

On the other hand, in the feedback control (FB control) of step S5, the feedback control signal is determined by the proportional / integral / derivative control (PID control) based on the deviation Err. Then, the final control duty is determined from the correction amount and the feedback control signal,
In the output process of step S6, the direction of the applied voltage (normal rotation /
(Reverse rotation) is determined to control the power supply to the motor 2.

The feedback control in step S5 may use a sliding mode control in addition to the proportional / integral / derivative control.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing an electric range switching device of an automatic transmission.

FIG. 2 is a perspective view showing a drive mechanism of a manual shaft.

FIG. 3 is a timing chart showing motor control characteristics.

FIG. 4 is a flowchart showing a main routine of motor control.

FIG. 5 is a flowchart showing a subroutine of control start / end determination control.

FIG. 6 is a flowchart showing a subroutine of shift progress state determination and control method selection control.

FIG. 7 is a timing chart showing characteristics of control start / end determination.

FIG. 8 is a diagram showing a correlation between load torque and manual shaft angle.

[Explanation of symbols]

1 ... Automatic transmission 2 ... motor 3 ... Reduction mechanism 4 ... Manual shaft 5 ... Detent mechanism 6 ... Manual valve 21 ... Potentiometer 22 ... Inhibitor switch 23 ... Range select switch 24 ... A / T control unit

Claims (5)

[Claims] 1. A structure in which a manual valve is driven by a manual shaft rotationally driven by a motor,
In an electric range switching device for an automatic transmission that drives and controls the motor so that the angle of the manual shaft becomes an angle corresponding to a required range, power supply to the motor is started to cope with a change in the required range. After that, the power supply to the motor is stopped when a predetermined ratio of the angle change width of the manual shaft corresponding to the change of the required range is reached, and thereafter it is necessary to reach the predetermined ratio of the angle change width. The power supply is stopped for a predetermined proportion of the time, and after the power supply stop time has elapsed, the motor is feedback-controlled so that the actual angle of the manual shaft becomes the angle corresponding to the required range. An electric range switching device for an automatic transmission, characterized in that 2. The electric transmission for an automatic transmission according to claim 1, wherein the control signal for the motor is held constant from the start of the power supply to the motor until the power supply is stopped. Range switching device. 3. In feedback control after the power supply stop time has elapsed, a feedback control amount according to a deviation between an actual manual shaft angle and a target angle corresponding to a required range, and inertia of the manual shaft. The electric range switching device for an automatic transmission according to claim 1 or 2, wherein the control signal for the motor is determined based on a correction amount according to the torque. 4. A correction amount according to the inertia torque,
The electric range switching device for an automatic transmission according to claim 3, wherein the determination is made based on a difference between the inertia torque at the time of stopping the power supply and the inertia torque released during the stop of the power supply. . 5. The feedback control is terminated when it is continuously determined that the actual angle of the manual shaft is within a predetermined angle range including the angle corresponding to the required range. The electric range switching device for an automatic transmission according to any one of 1 to 4.