KR19980047957A - 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 lever is changed from an N range to a D range; Outputting a corresponding duty control signal by setting an initial duty value, a duty gradient duty output time, and the like stored in the memory map when the shift lever is changed from an N range to a D range; Searching for the actual shift start point SB at which the RPM of the turbine becomes the RPM-20 of the maximum turbine by continuously inputting the RPM of the turbine from the time when the duty control signal is output as the duty control signal is output; When the actual shift start point SB is found above, the rate of change of the turbine by the set arithmetic equation Calculating a; Change rate value of turbine calculated above Calculating an error value by calculating the change rate value of the previously set turbine and the set arithmetic equation; Setting a correction duty value in a duty correction map stored in memory according to the error value calculated above, calculating the control duty value by calculating the current duty value and a set arithmetic expression, and outputting the control duty value as a corresponding signal; Determining whether the duty control signal has reached the shift completion time SF; If the duty control signal reaches the shift completion time SF, outputting a duty control signal for a preset hold time Ths; Determining whether an output time of the control duty control signal is greater than a set hold time (Ths) time as the duty control signal is further output during the hold time (Ths); When the output time of the actual duty control signal is greater than the set hold time (Ths) time, the step of ending all the duty control signals and return to the initial stage, the shift time when the shift lever conversion from the N range to the D range It is effective to improve the transmission feeling by making it constant, and to prevent the double shock, thereby improving the durability of the automatic transmission of the automatic transmission.

Description

Shift control method of automatic transmission

The present invention relates to a shift control method of an automatic transmission. More particularly, the present invention relates to a shift control method of an automatic transmission for reducing a shift shock generated when a quick start occurs after converting a shift lever of an automatic transmission from an N range to a D range. .

In general, a vehicle equipped with an automatic transmission controls the hydraulic pressure within a shift range set according to the driving 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 immature driving of the driver while driving.

Therefore, the automatic transmission is converted to a port according to the position selected by the driver's shift lever, and the fluid pressure is supplied from the oil pump, 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.

The selective operation of the friction element consisting of a clutch or a brake switches the operation of the planetary gear unit, which is then transmitted to the drive gear after an appropriate transmission ratio is made.

When the shifted power is transmitted to the drive gear, the shifted power is transmitted by a driven gear geared to the drive gear and driven to the driven gear geared to the gear reduction 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.

Therefore, to start driving a vehicle equipped with an automatic transmission that performs the above operation, conventionally, after converting the shift lever from the N range to the D range, the vehicle is subjected to an accelerator pedal in a state in which the shift of the automatic transmission is not completed. There was a case to depart.

However, the conventional technique described above, as shown in the accompanying Figure 1, after changing the shift lever of the automatic transmission from the N range to the D range, the clutch control hydraulic pressure is lowered due to the deviation or the hydraulic deviation of the transmission and the double shift shock occurs. At the same time, when the shift time becomes longer and the vehicle is started quickly by stepping on the accelerator pedal, there is a problem in that the shift shock is large and the durability of the automatic transmission is reduced.

Therefore, in order to solve the above-mentioned conventional problem, as shown in the accompanying FIG. 2, the fill time is measured by measuring the time from the time point at which the shift start command is issued to the time point SB at which the actual shift is made. Of the turbine and the rate of change of the turbine after the time of the actual shift (SB) The rate of change of the turbine Error is calculated by comparing with the above, and the duty correction value is calculated from the duty correction map shown in FIG. 5 to which the error value calculated above is attached and calculated with the current duty value. When the duty control signal reaches the completion time by performing the duty control and determining the shift completion time (SF), the duty signal is output for a predetermined time (Ths), and then all duty control is terminated, thereby shifting from the N range to the D range. It is to provide a shift control method of an automatic transmission having an effect of improving the shifting feeling by changing the shift time at the time of lever change and preventing the double shock to improve the durability of the automatic transmission.

The present invention for achieving the above object;

Determining whether the shift lever is varied from the N range to the D range;

Outputting a corresponding duty control signal by setting an initial duty value, a duty gradient duty output time, and the like stored in the memory map when the shift lever is changed from the N range to the D range;

Finding the actual shift start point (S.B) at which the turbine RPM becomes the maximum turbine RPM-20 by continuously inputting the RPM of the turbine from the time when the duty control signal is output as the duty control signal is output;

When the actual shift start point SB is found above, the rate of change of the turbine by the set arithmetic equation Calculating a;

The change rate value of the turbine calculated above (n)) has already set the change rate value ( calculating an error value by calculating by (o)) and a set arithmetic expression;

Setting a correction duty value in a duty correction map stored in memory according to the error value calculated above, calculating the control duty value by calculating a current duty value and a set arithmetic expression, and outputting the control duty value as a corresponding signal;

Determining whether the duty control signal reaches the shift completion time S.F;

Outputting a duty control signal for a preset hold time (Ths) when the duty control signal reaches a shift completion time (S.F);

Determining whether the output time of the actual duty control signal is greater than the set hold time Ths as the duty control signal is further output during the hold time Ths;

When the output time of the actual duty control signal is greater than the set hold time (Ths) time, it comprises the step of ending the mode duty control signal and returning to the initial stage.

1 is a shift control pattern of a conventional automatic transmission,

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

3 is 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 embodiment of the present invention;

5 is a duty compensation graph according to 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, which can be achieved and realized in detail by the above objects, will be described in detail with reference to the accompanying drawings.

A vehicle operation state detecting means (10) for receiving a signal that is varied in the state of the vehicle and outputs a corresponding electric signal according to an operation state of the vehicle;

The fill time is corrected by measuring the time from the time point SS at which the shift start command is issued to the time point SB at which the actual shift is made by receiving and reading a signal output from the vehicle operation state detecting means 10. The change rate of the turbine is measured after the time SB at which the actual shift is made, and the error is calculated by comparing with the change rate of the turbine which is already set, and the error value calculated above is calculated as the duty correction value in the duty correction map. By calculating with the current duty value, the duty control is performed according to the calculated duty control value and the shift completion time SF is determined. When the duty control signal reaches the completion time, the duty signal is output for a predetermined time Ths. Shift control means 20 when all duty control ends;

It consists of a driving means 30 for synchronizing the shift stage by receiving a duty control signal output from the shift control means 20.

In the above, the vehicle operating state detection means (10);

A throttle valve opening degree detection unit 11 for detecting an opening degree of a throttle valve whose opening and closing state is variable in association with an operation state of the accelerator pedal and outputting a corresponding signal;

A vehicle speed detector 12 which detects a driving speed of the vehicle and outputs a corresponding signal;

A shift lever detecting unit 13 for detecting a shift of a shift lever by a driver and outputting a corresponding signal;

A shift stage detecting unit 14 for detecting a variable state of the shift stage and outputting a corresponding signal when the shift stage is changed according to the throttle valve opening amount and the vehicle speed;

A turbine shaft rotational speed sensing unit 15 for sensing a rotational speed of the turbine shaft of the torque converter connected to the input shaft of the transmission and outputting a corresponding signal;

It consists of an engine speed detection unit 16 for detecting the rotational speed of the crankshaft variable according to the operating state of the engine and outputs a corresponding signal.

Therefore, in the shift control method of the automatic transmission according to the embodiment of the present invention, all the states in which the shift lever is changed from the N range to the D range or the R range are applied, but only the state when the shift lever is changed from the N range to the D range is described in detail. Explain.

The shift control means 20 determines whether the shift lever is changed from the N range to the D range (S100).

When the shift lever is changed from the N range to the D range, the shift control means 20 sets an initial duty value, a duty gradient duty output time, and the like stored in the memory map and outputs a corresponding duty control signal (S110). ).

As the duty control signal is output in the above, the shift control means 20 continuously inputs the RPM of the turbine from the time when the duty control signal is output, so that the actual shift starting point is the point where the RPM of the turbine becomes the RPM-20 of the maximum turbine. SB is found (S120).

When the shift control means 20 finds the actual shift start point SB in the above, the change rate of the turbine according to the set arithmetic expression ( ) Is calculated (S130).

However, if the actual shift start point (SB) is not reached in the above, that is, if the RPM of the turbine is not the maximum turbine RPM-20, the shift control means 20 until the actual shift starts the RPM of the shift turbine Enter to compare.

The rate of change of the turbine above ( ) Is calculated by dividing the result of subtracting the RPM value of the current turbine from the RPM value of all turbines by the operation period. ) Can be obtained.

The change rate value of the turbine calculated above (( The rate of change of the turbine ( o) and the calculated arithmetic equation to calculate an error value (S140).

The error value calculated above is expressed as an arithmetic expression as follows.

Error = ( ) o-( ) n

(here ( o is the rate of change of turbine RPM already set and stored in memory;

( n is the turbine RPM rate of change after the actual shift has started;

Error is a result obtained by subtracting the change rate of the turbine after the actual shift start from the preset turbine RPM change rate.

The error correction duty value is set in the duty correction map stored in the memory as shown in FIG.

The duty correction value set in the correction map is calculated with the current duty value to calculate the control duty value (S150).

The shift control means 20 outputs the duty control signal corresponding to the control duty value to the drive means 30 by the control duty value calculated above.

As the continuous duty control signal is output from the shift control means 20 determines whether the duty control signal reaches the shift completion time S.F (S160).

When the duty control signal reaches the shift completion time S.F, the shift control means 20 further outputs the duty control signal during the set hold time Ths.

However, when the duty control signal does not reach the shift completion time SF in the above, the shift control means 20 is a change rate of the turbine ( Return to step (S130) to calculate.

Therefore, the shift control means 20 determines whether the output time of the actual duty control signal is greater than the set hold time Ths time (S170).

When the output time of the actual duty control signal is larger than the set hallway time Ths time, the shift control means 20 ends all duty control signals and returns to the initial stage.

However, when the output time of the actual duty control signal is smaller than the set hold time Ths time, the shift control means 20 continues to output the duty control signal until it is larger than the set hold time Ths.

The above embodiments are described as the most preferred embodiments, and the present invention is not limited thereto, and the embodiments can be easily described from the above embodiments.

As described above, in the embodiment of the present invention, the time from the time point at which the shift start command is issued to the time point SB at which the actual shift is made is measured to correct the fill time, and the time point at which the actual shift is made (SB). The rate of change of the turbine after () n) and the rate of change ((( (o) is calculated by comparing an error value, and calculating the duty correction value from the duty correction map shown in FIG. 5 to which the error value calculated above is attached and calculating the current duty value. When the duty control signal reaches the completion time, the corresponding duty control is performed according to the value and the shift control completion time (SF) is determined. After the duty signal is output for a predetermined time (Ths), all duty control is terminated. It is possible to provide a shift control method of an automatic transmission having an effect of improving the shifting feeling by changing the shifting time to the range and improving the durability of the automatic transmission by preventing double shock.

Claims (10)

Determining whether the shift lever is varied from the N range to the D range; Outputting a corresponding duty control signal by setting an initial duty value, a duty equalizer duty output time, and the like stored in a memory map when the shift lever is changed from an N range to a D range; Searching for the actual shift start point (S.B) which is a point in time at which the turbine RPM becomes the maximum turbine RPM by continuously inputting the RPM of the turbine from the time when the duty control signal is output as the duty control signal is output; When the actual shift start point SB is found above, the rate of change of the turbine by the set arithmetic equation Calculating a; The change rate value of the turbine calculated above (n)) already set the rate of change of the turbine ( calculating an error value by calculating by (o)) and a set arithmetic expression; Setting a correction duty value in a duty correction map stored in memory according to the error value calculated above, calculating the control duty value by calculating a current duty value and a set arithmetic expression, and outputting the control duty value as a corresponding signal; Wow; Determining whether the duty control signal reaches the shift completion time S.F; Outputting a duty control signal for a preset hold time (Ths) when the duty control signal reaches a shift completion time (S.F); Determining whether the output time of the actual duty control signal is greater than the set hold time Ths as the duty control signal is further output during the hold time Ths; And if the output time of the actual duty control signal is greater than the set hold time (Ths) time, ending the mode duty control signal and returning to an initial stage. The method according to claim 1, If the actual shift start point (SB) is not reached in the above, that is, if the RPM of the turbine is not the maximum turbine RPM-20, the shift control means 20 changes the RPM of the shift turbine until the actual shift starts. A shift control method of an automatic transmission further comprising the step of comparing by input. The rate of change of the turbine according to claim 1 ) Is calculated by dividing the result of subtracting the RPM value of the current turbine from the RPM value of all turbines by the operation period. The shift control method of the automatic transmission made further comprising the step of calculating. The method according to claim 1, wherein the method of calculating the error value includes the calculated rate of change of the turbine (( The change rate value ((( and shifting the error value by subtracting from o). Error = ( ) o-( ) n (here ( o is the rate of change of turbine RPM already set and stored in memory; ( n is the turbine RPM rate of change after the actual shift has started; Error is a result obtained by subtracting the change rate of the turbine after the actual shift start from the preset turbine RPM change rate. The change rate of the turbine according to claim 1, wherein when the duty control signal does not reach the shift completion time SF, The shift control method of the automatic transmission comprising the step of returning to calculating). The shift control means 20 further includes continuously outputting the duty control signal until the output time of the actual duty control signal is smaller than the set hold time Ths. Shift control method of the automatic transmission made by. The method of claim 1, wherein the method for performing fill time correction is: If the error value calculated above is less than zero (-value), the fill time correction value is also less than zero (-value), and if the calculated error value is greater than zero (+ value), the fill time The shift control method of an automatic transmission, characterized in that for performing a correction larger than the correction value (+ value). The method of claim 1, wherein the method for performing initial duty correction comprises: If the error value calculated above is less than zero (-value), the initial duty correction value is corrected to be greater than zero (+ value), and if the calculated error value is greater than zero (+ value), the initial duty The shift control method of the automatic transmission, characterized in that the correction value is performed less than (-value) correction. The shift control method of an automatic transmission according to claim 1, wherein the fill time and the initial duty value are respectively corrected based on the calculated error value. The shift control method of an automatic transmission according to claim 1, wherein the fill time and initial duty value correction values calculated by the calculated error value are applied to the next D range shift in the N range.