KR100350131B1 - 2 →3 up shift control methode for automatic transmission - Google Patents

Abstract

In order to provide a shift control method during 2 → 3 upshift, which can prevent the excessive output due to shift pattern change and incorrect calculation of the run-up amount during the shift of 2 → 3 shifting, thereby obtaining a better shift feeling;

When 2 → 3 speed change is made under the oil temperature below a certain temperature, it is judged that the turbine speed is higher than the run-up limit, and if it is abnormal, the turbine speed is controlled to be lowered to the allowable RPM and then the normal shift control is performed. A control-up step;

If it is determined that the turbine rotation speed is above the run-up limit value, and judges that the turbine rotation speed is less than or equal to the tie-up control step, the duty control for preventing the tie-up is performed and the turbine rotation speed is raised to the allowable RPM. It's done,

When the turbine rotational speed is different from the allowable RPM even after the tie-up control step is performed in the tie-up control step, the vehicle is shifted to the initial stage of the run-up control means. Provides a shift control method.

Description

Shift control method at the time of 2 → 3 up shift of vehicle automatic transmission {2 → 3 UP SHIFT CONTROL METHODE FOR AUTOMATIC TRANSMISSION}

The present invention relates to a shift control method for a 2 → 3 upshift of a vehicular automatic transmission. More particularly, the present invention relates to a shift control method in which a run-up and tie-up phenomenon is immediately compensated for in a 2 → 3 upshift. It relates to a shift control method during 2 → 3 upshift.

For example, an automatic transmission applied to a vehicle is controlled by a shift control device controlling a plurality of solenoid valves to control hydraulic pressure according to a driving speed of a vehicle, an opening ratio of a throttle valve, and various detection conditions. To make the shift.

In other words, when the driver changes the select lever to the desired gear range, the manual valve port is changed and the hydraulic pressure supplied from the oil pump is selectively operated according to the duty control of the solenoid valve. Let this be done.

The automatic transmission operated according to this operating principle has a friction element that is deactivated in the operating state and a friction element that is converted from the deactivated state to the operating state when the shift to each target shift stage is executed. Since the shifting performance of the automatic transmission is determined according to the timing of deactivation and starting of the friction elements, recent studies on shift control methods for better shifting performance have been actively conducted.

In view of the technical background of the present invention, the shift control of the automatic transmission is upshift shift control in which the shift is sequentially performed from the first forward speed to the fourth speed according to the driving state of the vehicle, and the fourth forward to the first speed Downshift shift control in which shifting is sequentially performed and downskip shift control in which downshift is performed from 4 speed to 2 speed and 3 speed to 1 speed are performed.

In the shift control process according to the present invention in the above-described shift control process, conventionally, the turbine speed (engine rotational speed) control of the torque converter is calculated by the amount of run-up. Control is only possible by value.

However, when the turbine speed is controlled only by the correction value calculated by the run-up amount in the 2 → 3 shift control as described above, the excessive duty value due to incorrect calculation of the run-up amount is prevented. Since it is impossible to perform satisfactory duty correction for all conditions in which shifting occurs, that is, shift pattern change, throttle condition change, and the like, there is a problem in that there is a limit to control for improving the shift feeling.

Therefore, the present invention was invented to solve the above problems, and an object of the present invention is to prevent excessive output due to shift pattern change and incorrect calculation of the run-up amount in a 2 → 3 shifting process. The present invention provides a shift control method during a 2 → 3 upshift to obtain a good shift feeling.

1 is a shift system diagram to which the present invention is applied.

Fig. 2 is a graph of turbine operation at 2 → 3 upshift

3 is an operational flowchart according to the present invention.

In order to realize this, the present invention provides a control method in which a control step at run-up and a control step at tie-up are combined when a shift speed of 2 → 3 is achieved while the oil temperature is below a predetermined temperature.

That is, when 2 → 3 speed change is made in the state where oil temperature is below a certain temperature, it is judged whether or not the turbine rotation speed is higher than the run-up limit value. A run-up control step;

If it is determined that the turbine rotation speed is above the run-up limit value, and judges that the turbine rotation speed is less than or equal to the tie-up control step, the duty control for preventing the tie-up is performed and the turbine rotation speed is raised to the allowable RPM. It's done,

When the turbine rotational speed is different from the allowable RPM even after performing the tie-up control in the tie-up control step, the vehicle is shifted to the initial stage of the run-up control means. Provides a shift control method.

The run-up control step may include a first step of determining whether the oil temperature is equal to or greater than a predetermined value;

If it is determined in the first step that the oil temperature is equal to or less than the reference value, a second step of determining whether the current turbine rotational speed is greater than the run-up limit value at the time of 2 → 3 shifting input to the map table;

A third step of reading a reference duty value required for 2 → 3 speeds when determined to be large in the second step;

A fourth step of judging whether the current state needs to be changed in the shift pattern after the execution of the third step;

If it is determined that the shift pattern change is necessary in the fourth step, a fifth step of outputting in a state where a reference duty value and a duty value according to the shift change are added;

A sixth step of determining whether the turbine speed is equal to the allowable RPM input to the map table after the fifth step;

A seventh step of performing normal control by outputting a reference duty value if it is determined to be the same in the sixth step;

If it is determined that there is a difference in the sixth step, the eighth step of returning to the first step after outputting the reference duty value and the duty value according to the shift change is made,

If it is determined that the shift pattern change is not necessary in the fourth step, the process proceeds to the sixth step.

The tie-up control step may include a first step of outputting a reference duty value and a tie-up prevention duty value;

A second step of determining whether the turbine speed is less than 2 → 3 tie-up limit value after the first step;

A third step of outputting a reference duty value and a tie-up prevention duty value again when it is determined as small in the second step;

A fourth step of determining whether the turbine speed is equal to the allowable RPM input to the map table after the third step;

If it is determined that the same in the fourth step, the fifth step of performing a normal control by outputting a reference duty value,

If it is determined in the second step that the turbine speed is greater than the 2 → 3 tie-up limit value, the process proceeds to the fifth step. If the turbine speed is determined to be different from the allowable RPM input to the map table in the fourth step, the Return to the initial stage of the up-control phase.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can realize the above object will be described in detail.

1 is a shift control system diagram of an automatic transmission, in which a rotation speed of a turbine on an output side is detected and input to a shift control unit 30 when a rotational power is output by torque conversion from the engine 10 through a torque converter 20, The vehicle state, the throttle opening rate, the oil temperature, and the like may be detected from the driving state detector 40, and an electrical signal corresponding thereto may be input to the shift controller 30.

Then, the transmission control unit 30 determines the overall driving state of the vehicle by the signal applied from the driving state detecting unit 40, and outputs a signal of the duty pattern for the hydraulic control based on the data of the set map table, the hydraulic system Will drive (50).

The hydraulic system 50 controls each friction element by driving each solenoid valve for shift stage synchronization according to a control signal applied from the shift control unit 30, thereby controlling the opening degree of the throttle valve and the vehicle speed and torque converter. According to the turbine rotational speed in the target shift stage is to perform the up shift or down shift.

In such a control system, it is ideal for the hydraulic control system to smoothly change the rotation speed of the turbine when controlling the engagement and release of the friction element.

That is, as shown in FIG. 2, in the process of shifting from second to third speed, the turbine rotation speed Nt is at a speed set to a predetermined reference value from the shift start timing SS to the shift completion timing SF as in a solid line. Only when shifting is carried out while decelerating, shift shocks do not occur.

However, if the control is not performed properly, run-up occurs as the speed of the initial turbine speed is increased from the reference value like the one-dot chain line, or a tie-up phenomenon occurs when it falls below the reference value, such as the double-dot chain line.

When the run-up or tie-up phenomenon occurs in the shifting process as described above, the shifting feeling decreases due to shifting shock, etc. At this time, more effective shift control should be made.

Accordingly, the present invention determines whether the oil temperature is a predetermined value or more in the process of shift control as in FIG. 3 when shifting 2 → 3 (S100).

If it is determined in step S100 that the oil temperature is equal to or less than the reference value (approximately 20 ° C.), it is determined whether the current turbine rotation speed Nt is greater than the run-up limit value at the time of 2 → 3 shifting input in the map table. (S110).

If it is determined in step S110 that the turbine speed Nt is greater than the 2 → 3 run-up limit value, after reading the reference duty value required for 2 → 3 speed (S120), it is determined whether the current state requires the shift pattern to be changed. If it is determined (S130) that it is determined that the shift pattern change is necessary, the output is made in a state in which the reference duty value and the duty value according to the shift change are added (S140).

In the state where the duty value output in step S140 is controlled, it is determined whether the turbine rotation speed Nt is equal to the allowable RPM input to the map table (S150). If it is determined to be the same, the reference duty value is output to normal control. It will be carried out (S160).

If it is determined that the shift pattern change is not necessary in step S130, the process proceeds to step S150. If it is determined that the turbine rotation speed Nt is different from the allowable RPM in step S150, the reference duty value and the shift change are again performed. The duty value is output (S170), and the process returns to step S110.

That is, in the control process from step S110 to step S170, when the turbine rotation speed exceeds the run-up limit value and changes the shift pattern, the limit value, that is, a correction value according to ΔNt is added to the basic duty value to control the oil pressure of the friction element, The fastening of the friction elements allows the turbine speed to return to stability and then normal control.

If it is determined in step S110 that the turbine speed Nt is smaller than the 2 → 3 run-up limit value, the reference duty value and the tie-up prevention duty value are output (S200), and then the turbine speed Nt is controlled. Is determined to be smaller than the 2 → 3 tie-up limit value (S210). If it is determined to be smaller, the reference duty value and the tie-up prevention duty value are output again (S220) to control.

In the state where control is performed with the duty value output in step S220, it is determined whether the turbine rotation speed Nt is the same as the allowable RPM input to the map table (S230). It will be carried out (S240).

If it is determined in step S210 that the turbine speed Nt is greater than the 2 → 3 tie-up limit value, the reference duty value is output and normal control is performed (S20). In step S230, the turbine speed Nt is determined. If it is determined that there is a difference between the allowed RPM input to the map table, the control returns to step S110 is made.

That is, the control process from step S200 to step S240 suggests a control method when the tie-up phenomenon occurs. If it is determined that the tie-up phenomenon has occurred, a compensation value for preventing tie-up to the basic duty value is determined. In addition, by controlling the hydraulic control system, by loosening the fastening state of the pre-fastening friction elements to ensure that the turbine rotation speed is restored to the normal control can be made again.

As described above, according to the control method of the present invention, when the shift speed is 2 → 3 when the oil temperature is lower than the predetermined temperature, it is determined whether the turbine rotation speed is greater than the run-up limit value and the turbine rotation speed drops to the allowable RPM when it is determined to be abnormal. After the control, the normal shift control is carried out, and in the event of a tie-up phenomenon, a duty control is performed to prevent the tie-up. It is an invention that a better shifting feeling can be obtained by preventing excessive output due to shift pattern change and incorrect calculation of the run-up amount in the 2 → 3 shifting process.

Claims (4)

When 2 → 3 speed change is made under the oil temperature below a certain temperature, it is judged that the turbine speed is higher than the run-up limit, and if it is abnormal, the turbine speed is controlled to be lowered to the allowable RPM and then the normal shift control is performed. A control-up step; If it is determined that the turbine rotation speed is above the run-up limit value, and judges that the turbine rotation speed is less than or equal to the tie-up control step, the duty control for preventing the tie-up is performed and the turbine rotation speed is raised to the allowable RPM. It's done, When the turbine rotational speed is different from the allowable RPM even after performing the tie-up control in the tie-up control step, the vehicle is shifted to the initial stage of the run-up control means. Shift control method. The method of claim 1, wherein the run-up control step comprises: a first step of determining whether the oil temperature is equal to or greater than a predetermined value; If it is determined in the first step that the oil temperature is equal to or less than the reference value, a second step of determining whether the current turbine rotational speed is greater than the run-up limit value at the time of 2 → 3 shifting input to the map table; A third step of reading a reference duty value required for 2 → 3 speeds when determined to be large in the second step; A fourth step of judging whether the current state needs to be changed in the shift pattern after the execution of the third step; If it is determined that the shift pattern change is necessary in the fourth step, outputting the reference duty value and the duty value according to the shift change in a state of adding; A sixth step of determining whether the turbine speed is equal to the allowable RPM input to the map table after the fifth step; A seventh step of performing normal control by outputting a reference duty value if it is determined to be the same in the sixth step; If it is determined that there is a difference in the sixth step, the eighth step of returning to the first step after outputting the reference duty value and the duty value according to the shift change is made, If it is determined that the shift pattern change is not necessary in the fourth step, the shift control method at the time of 2 → 3 upshift of the automatic transmission for a vehicle, characterized in that proceeds to the sixth step. The method of claim 1, wherein the tie-up control step comprises: a first step of outputting a reference duty value and a tie-up prevention duty value; A second step of determining whether the turbine speed is less than 2 → 3 tie-up limit value after the first step; A third step of outputting a reference duty value and a tie-up prevention duty value again when it is determined as small in the second step; A fourth step of determining whether the turbine speed is equal to the allowable RPM input to the map table after the third step; If it is determined that the same in the fourth step, the fifth step of performing a normal control by outputting a reference duty value, If it is determined in the second step that the turbine speed is greater than the 2 → 3 tie-up limit value, the process proceeds to the fifth step. If the turbine speed is determined to be different from the allowable RPM input to the map table in the fourth step, the The shift control method at the time of 2 → 3 upshift of the vehicular automatic transmission, characterized by being returned to the initial stage of the up-control phase. A first step of determining whether the oil temperature is above a predetermined value; If it is determined in the first step that the oil temperature is equal to or less than the reference value, a second step of determining whether the current turbine rotational speed is greater than the run-up limit value at the time of 2 → 3 shifting input to the map table; A third step of reading a reference duty value required for 2 → 3 speeds when determined to be large in the second step; A fourth step of judging whether the current state needs to be changed in the shift pattern after the execution of the third step; If it is determined that the shift pattern change is necessary in the fourth step, outputting the reference duty value and the duty value according to the shift change in a state of adding; A sixth step of determining whether the turbine speed is equal to the allowable RPM input to the map table after the fifth step; A seventh step of performing normal control by outputting a reference duty value if it is determined to be the same in the sixth step; If it is determined that there is a difference in the sixth step, an eighth step of outputting a reference duty value and a duty value according to a shift change, and then returning to the first step; A ninth step of outputting a reference duty value and a tie-up prevention duty value when it is determined that the turbine rotational speed is equal to or less than 2 → 3 run-up in the second step; A tenth step of determining whether the turbine rotational speed after the ninth step is smaller than a 2 → 3 tie-up limit value; An eleventh step of outputting a reference duty value and a tie-up prevention duty value again when it is determined in the tenth step; A twelfth step of determining whether the turbine rotational speed is equal to the allowable RPM input to the map table after the eleventh step; If it is determined that the same in the twelfth step, the thirteenth step of performing a normal control by outputting a reference duty value, If it is determined that the shift pattern change is not necessary in the fourth step, the process proceeds to the sixth step. If it is determined in the tenth step that the turbine rotational speed is greater than the 2 → 3 tie-up limit value, the process proceeds to the thirteenth step. If it is determined in step 12 that the turbine rotation speed is different from the allowable RPM input to the map table, the shift control method at the time of 2 → 3 upshift of the automatic transmission for a vehicle, characterized in that the step 12 is returned.