KR19980045420A - Shift control method of automatic transmission - Google Patents

Abstract

The present invention relates to a shift control method of an automatic transmission, comprising: determining whether a shift stage is in a power on-down shift shift; Setting a reference duty output time of section A, which is a shift synchronization section, and outputting a corresponding duty control signal by setting an initial duty value and a duty gradient stored in a memory map; Calculating the RPM of the section A current turbine by a set formula, and comparing the calculated value with the set reference turbine RPM; When the RPM of the output turbine is greater than or equal to the RPM of the turbine set in the reference turbine, stopping the duty output of section A, setting the reference duty output time corresponding to section B and outputs the corresponding duty control signal Wow; Calculating the turbine RPM output by the set arithmetic expression and comparing the set reference turbine RPM β when the duty control signal of section B is output; If the output RPM of the turbine is greater than or equal to the set reference turbine RPM β, it is determined that the shift synchronization is completed and the output of the duty control signal in section B is stopped and the reference duty output time corresponding to section C is set. Outputting a corresponding duty control signal; When the output time of the duty control signal output from the output of the duty control signal is greater than the set reference duty control signal compared to the set reference duty output time, the step of ending the output of all the duty control signal to return to the initial step When the vehicle is equipped with an automatic transmission that senses the engine, turbine RPM, vehicle speed, and can be hydraulically controlled by duty control, when the accelerator pedal is pressed to increase speed while driving, the shift is made due to the occurrence of shift synchronization. Calculate the RPM of the turbine output after a certain time in consideration of the response characteristics of the hydraulic pressure and compare it with the RPM of the reference turbine set, compensating for the duty value according to the RPM difference of the compared turbine above, the control pressure duty control slope Reduced shift shocks generated at the end of shifts by adding one feedback effect The memory capacity of the shift control means can be reduced.

Description

Shift control method of automatic transmission

The present invention relates to a shift control method of an automatic transmission. More specifically, when a kick-down shift in which a shift stage is powered on and down shifted from a high stage to a low stage by pressing an acceleration pedal during driving, a feed back is performed by simple control. The present invention relates to a shift control method of an automatic transmission for reducing feed shock by effecting a feed back effect.

In general, a vehicle equipped with an automatic transmission controls the hydraulic pressure within a shift range set according to the traveling speed of the vehicle so that the shift gear of the target shift stage may be automatically operated.

Therefore, the torque converter is operated according to the output power of the engine to control the rotational force of the fluid, and according to the control signal applied from the shift controller so that the shift gear according to the operating state of the vehicle can be operated. Hydraulic pressure acts on the valve to allow shifting.

Therefore, a vehicle equipped with an automatic transmission in which the operating state is controlled according to the hydraulic pressure does not require the operation of a clutch pedal to cut off power from the engine in order to change the operating state of the corresponding shift gear. Fatigue can be reduced, and an engine stall does not occur due to malfunction or inexperience of a driver while driving, so that even a beginner can easily operate a driving operation.

Therefore, the automatic transmission receives a fluid pressure from the oil pump by changing the port according to the selected position of the driver's shift lever, and the operating state of the hydraulic valve is changed by the fluid pressure so that any one of the gear stages of the transmission gear mechanism is shifted. Controls the operating state of the hydraulically actuated friction element for selecting stages.

According to the selective operation of the friction element, which consists of a clutch or a brake, the operation of the planetary gear device is switched, and an appropriate transmission ratio is then transmitted to the drive gear.

When the shifted power is transmitted to the drive gear, the shifted power is transmitted to the driven gear which is geared to the longitudinal reduction gear by the driven gear which is geared to the drive gear to control the rotational operation of the wheel.

As described above, the target shift stage is determined according to the driving state of the vehicle, and when the control operation to the determined target shift stage is executed, the corresponding friction element is operated for each target shift stage among friction elements consisting of a clutch or a brake. Let's do it.

As shown in FIG. 1, when the accelerator pedal is pressed to increase speed in a vehicle driving in an automatic transmission, the shift stage is kicked down from 5 speed to 3 speed, shifted to 3 speed, and driven accordingly. In the duty control, the hydraulic pressure was controlled by outputting a duty control signal at a slope of two stages with a certain duty control time from the time when the shift command is generated.

However, the conventional technique described above turns on the accelerator pedal while driving at 5 speeds, whereby the gear shifting kick occurs at 3 speeds. At this time, the throttle opening degree increases from 0% to 100%, and the control logic is OWC (one Since there is a way clutch, it controls the hydraulic pressure to release the clutch, but there is a problem that a shift shock occurs at the end of the shift.

In addition, since the duty control for synchronizing the target shift stage is controlled with two levels of inclination, accurate duty control is difficult, and there is a problem that a change in shifting feeling occurs due to hydraulic deviation.

Accordingly, an object of the present invention is to solve the problems of the prior art described above, by detecting an engine, a turbine RPM, and a vehicle speed, the accelerator pedal may be stepped while driving in a vehicle equipped with an automatic transmission capable of hydraulic control by duty control. At this time, if the shift is made due to shift synchronism, the duty value is compensated according to the RPM difference of the output turbine by calculating the RPM of the turbine after a predetermined time in consideration of the hydraulic response characteristics and comparing it with the RPM of the set reference turbine. The present invention provides a shift control method of an automatic transmission for reducing a shift shock generated at the end of a shift by adding a control pressure duty control slope to give a feedback effect.

The present invention for achieving the above object comprises the steps of determining whether the shift stage is a power on down shift shift; Setting a reference duty output time of section A, which is a shift synchronization section, and outputting a corresponding duty control signal by setting an initial duty value and a duty gradient stored in a memory map; Calculating the RPM of the section A current turbine by a set formula, and comparing the calculated value with the set reference turbine RPM; When the RPM of the output turbine is greater than or equal to the RPM of the set reference turbine, the duty output of section A is stopped and the reference duty output time corresponding to section B and the duty slope are set to output the corresponding duty control signal. Making a step; Calculating the turbine RPM output by the set arithmetic expression and comparing the set reference turbine RPM β when the duty control signal of section B is output; If the output RPM of the turbine is greater than or equal to the set reference turbine RPM β, it is determined that the shift synchronization is completed and the output of the duty control signal in section B is stopped, and the reference duty output time and duty slope corresponding to section C are stopped. Setting a and outputting a corresponding duty control signal; The output sin is compared with the set reference duty output time when the output time of the duty control signal outputted above is greater than the set reference duty control signal, and the output sin terminates the output of all the duty control signals and returns to the initial stage. It is done.

1 is an automatic transmission shift control pattern of the prior art,

2 is a shift control pattern of an automatic transmission according to an embodiment of the present invention,

3 is a block diagram of a shift control apparatus of an automatic transmission according to an embodiment of the present invention;

4 is a flowchart illustrating a shift control method of an automatic transmission according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention that can specifically realize the above objects are described in detail with reference to the accompanying drawings.

As shown in FIG. 3, a configuration of a shift control apparatus of an automatic transmission according to an exemplary embodiment of the present invention includes: a vehicle driving state sensing means 10 for outputting a signal that varies according to a driving state of a vehicle; When the shift synchronization is generated by receiving the signal output from the vehicle driving state detecting means 10, after a predetermined time, the turbine RPM is calculated and compared with the set reference turbine RPM, and the RPM calculated and compared in the above A shift control means 20 for correcting and outputting a duty control signal of a corresponding section when the RPM is greater than or equal to the RPM of the set reference turbine to prevent shift shock occurring at the end of the shift; It consists of a drive means 30 including a solenoid valve for adjusting the hydraulic pressure in accordance with the duty control signal output from the shift control means 20.

In the above, the vehicle driving state detection means 10, the throttle opening degree detection unit 11 for detecting the opening degree of the throttle valve whose opening and closing state is variable according to the operation of the accelerator pedal and outputs a corresponding electric signal; A vehicle speed detector 12 which detects a speed of a driving vehicle and outputs a corresponding electric signal; An engine rotation speed detection unit 13 for detecting a rotational speed of the crankshaft which is varied according to an operating state of the engine and outputting a corresponding electric signal; Turbine shaft rotation speed detection unit 14 for detecting the rotational speed of the turbine side of the torque converter connected to the input side of the transmission and outputs a corresponding electric signal.

By the above configuration, the operation of the shift control method in the automatic transmission according to the embodiment of the present invention is as follows.

When the accelerator pedal is pressed in order to further increase the speed in the driving vehicle, the shift control means 20 determines, for example, whether the shift stage is in power on downshift (kick down shift) from 5 to 3 speed (S100). .

If the shift stage is downshifting before stepping on the accelerator pedal, the shift is continuously performed.

However, when the shift stage generates a kick-down shift by depressing the accelerator pedal, the shift control means 20 sets the point of time as the shift synchronization occurrence point and calculates the result after the initial duty value and temperature compensation stored in the memory. The corresponding duty control signal is output by setting a reference duty output time T1 corresponding to section A and setting a duty gradient in the power-on down shift map by calculating a value corresponding to the value S (S100).

The solenoid valve of the drive means 30 is controlled according to the duty control signal output from the above.

When a predetermined time has elapsed since the shift synchronizing occurs, the shift control means 20 calculates the turbine RPM output by the set arithmetic expression, and the reference value set for the calculated output turbine RPM and duty control calculated above. Compared with the turbine RPM α (S120)

The arithmetic expression for calculating the turbine RPM calculated and output by the arithmetic formula set by the shift control means 20 and comparing it with the set reference turbine RPM is expressed by the following formula.

N _T -N _Ti

------ ≥ α (α × 100 = α%)

N _TO -N _Ti

Where N _T is the current turbine RPM, N _Ti is the full gear ratio × N _O , N _TO is the gear ratio × N _O , N _O is the vehicle speed, and α is variable depending on the driving conditions of the vehicle. Constant.)

Therefore, when the arithmetic result of the output RPM of the turbine is greater than or equal to the set reference value or when the T1 setting time has elapsed, it is determined that the duty output of section A is completed (S120), and the duty of section A is completed. The output is stopped, the reference duty output time T2 corresponding to the section B is set, and the duty control signal corresponding to the section B is output (S130).

However, if the arithmetic result of the output RPM of the turbine is smaller than the set reference value, the duty control signal of section A is continuously output until the arithmetic result of the output RPM of the turbine is greater than or equal to the set reference value. (S121).

The duty slope '1' of the A section is controlled simultaneously from the time when the shift synchronization occurs.

Therefore, when the duty control signal of the B section is output after the duty control signal of the A section is completed, the RPM of the turbine output to the B section is calculated by the set arithmetic expression, and the calculated result is higher than the set reference value β. It is determined whether or not the same (S140).

The arithmetic expression comparing the output turbine RPM of the B section calculated and calculated above with the RPM of the set reference turbine is expressed by the following equation.

Where N _T is the current turbine RPM, N _Ti is the full gear ratio × N _O , N _TO is the gear ratio × N _O , N _O is the vehicle speed, and β is variable depending on the driving condition of the vehicle. Constant.)

When the arithmetic result of the RPM of the turbine of section B output above is greater than or equal to the set reference value β, the output of the duty control signal of section B is stopped and the output time T3 of the reference duty control signal corresponding to section C is stopped. Set and output a duty control signal corresponding thereto (S150).

However, if the RPM of the turbine of section B output from the above is smaller than the set reference turbine RPM β, the shift control means 20 calculates the change in the RPM of the turbine in section B and determines whether the change is smaller than the set value C (S141).

When the change in RPM of the turbine is calculated in section B and the change is smaller than the set value C, the shift control means 20 determines that the duty output in section B is completed, and stops the duty output in section B, The reference duty output start time T3 of the C section is set to output the corresponding duty signal (S150).

The method for calculating the RPM change of the turbine is as follows.

N _Tn -N _Tn-1 C

Where N _Tn is the turbine RPM currently being output,

N _Tn-1 is the previous RPM of the turbine currently being output,

C is the turbine RPM change setpoint.)

However, when the calculated turbine RPM is greater than the RPM C of the set reference turbine, the shift control means 20 determines whether the actual duty output time is greater than the set reference duty output time T2 in the section B (S142).

When the actual duty output time of the section B is greater than the set reference duty output time T2, the shift control means 20 stops the duty output of the section B, and outputs the duty control signal of the section C by the set reference duty control signal. Output (S150).

That is, the calculated RPM of the turbine output in section B is calculated and the calculated result is greater than or equal to the set reference value β, or the change in the RPM of the turbine in section B, the change is less than the set value C, If the actual duty output time of the B section is greater than the set reference duty output time T2, the duty control signal of the C section is output.

Therefore, if only one of the above three is satisfied, it moves to section C immediately.

However, when the duty output time output in the B section is smaller than the set reference duty output time T2, the duty control signal in the B section is continuously output (S143).

As described above, when the output of the duty control signal in section B is stopped and the duty control signal in section C is output from the shift control means 20, the reference duty output time in which the output time of the duty control signal actually output in section C is set is set. It is determined whether greater than T3 (S160).

When the duty output time output in the C section is greater than the set reference duty output time T3, all duty output ends and returns to the initial stage.

However, if the actual duty output time of section C is smaller than the set reference duty output time T3, the duty control signal corresponding to section C is continuously output until the set reference duty output time T3 is exceeded (S161).

The most preferred embodiments have been described in the above-described embodiments, and the present invention is not limited thereto, and the invention can be easily invented from the above embodiments.

As described above, in an embodiment of the present invention, the accelerator pedal may be pressed to increase the speed while driving in a vehicle equipped with a JX-A / T automatic transmission that is capable of hydraulic control by duty control by detecting an engine, turbine RPM, and vehicle speed. At this time, when the shift is made due to shift synchronism, the RPM of the output turbine is calculated after a certain time in consideration of the hydraulic response characteristics, and compared to the RPM of the reference turbine set, and the difference in the RPM of the compared turbine is compared. The automatic transmission has the effect of reducing the shift shock generated at the end of the shift and reducing the memory capacity of the shift control means by compensating the duty value and adding one control pressure duty control slope to give a feedback effect. The shift control method can be provided.

Claims (7)

Determining whether the shift stage is in power on-down shift shifting; Setting a reference duty output time of section A, which is a shift synchronization section, and outputting a corresponding duty control signal by setting an initial duty value and a duty gradient stored in a memory map; Calculating the RPM of the section A current turbine by a set formula, and comparing the calculated value with the set reference turbine RPM; If the RPM of the output turbine is greater than or equal to the RPM of the set reference turbine, or if the duty setting time has elapsed after judging whether the A duty cycle reference duty output time has been set, the duty cycle of the A section is stopped and the B section Setting a reference duty output time corresponding to and outputting a corresponding duty control signal; When the duty control signal of section B is output, the calculated RPM of the turbine output to section B is calculated and the calculated result is greater than or equal to the set reference value β or the change of RPM of turbine in section B If the change is smaller than the set value C or the actual duty output time of the section B is larger than the set reference duty output time T2, it is determined that the shift synchronization is completed and the output of the duty control signal of the section B is stopped. Setting a reference duty output time to output a corresponding duty control signal; Comparing the output time of the duty control signal outputted above with the set reference duty output time, when the output duty control signal is larger than the set reference duty control signal, ending the output of all duty control signals and returning to the initial stage; Shift control method of an automatic transmission, characterized in that comprises a. { Where N _T is the current turbine RPM, N _Ti is the gear ratio × N _O N _TO is the gear ratio × N _O N _O is the speed of the car, β is a constant that varies depending on the driving state of the vehicle to be.) Or N _Tn -N _Tn-1 C Where N _Tn is the turbine RPM currently being output, N _Tn-1 is the previous RPM of the turbine currently being output, C is the turbine RPM change set point to be.) Or T T2 Where T is the duty output time for section B, T2 is the reference duty output time set in section B. to be.) } The method of claim 1, wherein when the output turbine RPM of section A is smaller than the set reference turbine RPM α, the duty control signal of the section is continued until the calculated result of the output turbine RPM of section A is greater than or equal to the set reference value α. A shift control method of an automatic transmission, including outputting. The duty cycle of the section B according to claim 1, wherein the calculated result of the output turbine RPM of section A is greater than or equal to the set reference value α, or the set duty output time T1 of section A is less than the output time T1 to output. A shift control method of an automatic transmission, comprising performing control. The method of claim 1, wherein when the RPM of the turbine calculated and outputted in section B is smaller than the set reference turbine RPM β, the turbine RPM change in section B is calculated to determine whether the calculated value is smaller than the RPM change value C of the set turbine. Judging; In the case where the RPM change value of the turbine section B is smaller than the RPM change value C of the set turbine, the output of the duty control signal in section B is stopped, the reference duty output time corresponding to section C is set, and the corresponding duty control signal is set. The shift control method of the automatic transmission comprising the step of outputting. {N _Tn -N _Tn-1 C Where N _Tn is the RPM of the turbine currently being output, N _Tn-1 is the previous RPM of the turbine currently being output, C is the turbine RPM change set point to be.) } The method of claim 4, wherein when the calculated RPM change value of the turbine is greater than or equal to the set RPM change value C of the turbine, it is determined whether the output time T of the duty control signal in section B is greater than the set reference duty control signal output time T2. Steps; When the output time of the duty control signal of section B is greater than the output time of the set reference duty control signal, the output of the duty control signal of section B is stopped and the reference duty output time corresponding to section C is set. And a step of outputting a corresponding duty control signal. T T2 Where T is the duty output time for section B, T2 is the reference duty output time set in section B. to be.) The method of claim 5, wherein when the output time of the duty control signal of section B is less than or equal to the output time of the set reference duty control signal, until the output time of the duty control signal of section B is greater than the set reference duty output time. A shift control method of an automatic transmission comprising a step of continuously outputting a duty control signal of the section B. The shift control method of claim 1, further comprising: continuously outputting a duty control signal corresponding to the C section when the duty output time of the C section is less than or equal to the set reference duty output time.