KR19980045476A - 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 in an N range or an R range immediately after a driver starts a vehicle; Determining whether the shift lever is changed from the N range to the D range for the first time after the engine is started, when the shift lever is in the N range or the P range; When the shift lever is changed from the N range to the D range for the first time after starting the engine, the maximum fill time T3α and the initial duty stored in the correction map of the memory are set separately, and the preset fill time Ta is set. And calculate the fill time (Ft) by calculating the maximum correction fill time (T3α) set by the set arithmetic formula to perform the fill time for the corresponding time and output the duty control signal by the initial duty set above. It is composed of the following steps, and the effect is to reduce the shift shock that occurs when driving after converting from the N range to the D range or R range immediately after the engine is started, and the shift shock that occurs when the vehicle stays in the N range for more than a set time and then switches to the D range There is.

Description

Shift control method of automatic transmission

The present invention relates to a shift control method of an automatic transmission, and more particularly, to reduce a shift shock that occurs when a shift lever is changed from an N range or a P range to a D range after starting to drive a vehicle. It relates to a shift control method of an automatic transmission.

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 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 position selected by the driver's shift lever, and the operating state of the hydraulic valve is changed by the fluid abar so that any gear stage 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 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.

Conventionally, the vehicle operated by the above operation is started by converting the shift lever from the N range or the P range to the D range immediately after starting.

However, the conventional technique described above is a transmission oil on the drive flow path of the D range of the automatic transmission when the shift lever is changed from the N range or the P range to the D range immediately after the engine is started. There is a problem in that the time until the oil is filled on the drive passage after exiting is long, and thus a response delay and a shift shock occur.

In addition, the shift response delay and shift shock occurs when the shift lever is shifted from the D range to the N range and continues to be set for more than the set time and then shifts the shift lever back to the D range as described above.

Therefore, in order to solve the above-mentioned conventional problems, when converting the first shift lever from the N range to the D range or the R range after starting the engine, the fill time and the initial duty value are set separately to improve the shift response delay and Improves the feeling of shifting, converts from N range to D range, selects fill time correction value and correction duty according to the time stayed in the N range during shifting of the shift stage, and performs fill time correction and duty correction, so that N range immediately after engine startup To provide a shift control method of an automatic transmission that has an effect of reducing shift shock generated when driving after converting from the D range to the D range or the R range, and staying in the N range for more than a set time, and then converting to the D range. will be.

The present invention for achieving the above object comprises the steps of determining whether the position of the shift lever is the N range or R range immediately after the driver starts the vehicle; Determining whether the shift lever has been converted from the N range to the D range for the first time after starting the engine, when the shift lever is in the N range or the P range; When the shift lever is changed from the N range to the D range for the first time after starting the engine, the maximum fill time T3α and the initial duty stored in the correction map of the memory are set separately, and the preset fill time Ta is set. And calculate the fill time (Ft) by calculating the maximum correction fill time (T3α) set by the set arithmetic formula to perform the fill time for the corresponding time and output the duty control signal by the initial duty set above. It is characterized by consisting of steps.

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

2 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, which can be achieved and realized in detail by the above objects, will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, a configuration of a shift control apparatus for an automatic transmission according to an exemplary embodiment of the present invention is configured to output a corresponding electric signal by receiving a signal that is output by varying the state of the vehicle according to an operation state of the vehicle. Vehicle operation state detection means (10); After receiving the signal output to the vehicle operation state detection means 10 by reading the engine when the first shift lever from the N range to D range or R range after setting the fill time (Fill Time) and the initial duty value separately Improves shift response delay and improves the feeling of shifting, converts from N range to D range, and selects fill time correction value and correction duty according to the time stayed in N range when shifting the shift stage to perform fill time correction and duty correction. Shift control means 20 for outputting a control signal; It consists of a drive 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 operation state detection means 10, the throttle valve actuation detection unit 11 for detecting the degree of opening of the throttle valve whose opening and closing state is variable in conjunction with the operation state of the accelerator pedal and outputs a corresponding signal; A vehicle speed detector 12 which detects a driving speed of the vehicle and outputs a corresponding signal; A shift stage sensing unit 13 configured to detect a variable state of the shift stage and output a corresponding signal when the shift stage is changed according to the throttle valve opening amount and the vehicle speed; An engine rotation speed detection unit 14 for detecting a rotation speed of the crankshaft which is varied according to an operating state of the engine and outputting a corresponding signal; 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; The shift lever detection unit 16 detects that the shift lever position is changed by the driver and outputs a corresponding signal.

The present invention is applied to the case where the shift lever is converted from the N range or the P range to the D range or the R range, but the following description will be given by taking an example of converting from the N range to the D range.

When the driver shifts the shift lever from the N range to the D range and presses the accelerator pedal immediately after the vehicle is started to go to the place where the driver intends to go, the shift control means 20 starts the vehicle. Immediately after turning on, it is determined whether the shift lever is in the N range or the R range (S100).

When the shift lever is in the N range or the P range, the shift control means 20 determines whether the shift lever is first changed from the N range to the D range after the engine is started (S110).

When the shift lever is first converted from the N range to the D range after the engine is started, the shift control means 20 sets the maximum correction fill time T3α and the initial duty separately stored in the correction map of the memory. By calculating the fill time by calculating the preset fill time Ta and the maximum correction fill time set by the arithmetic equation, the fill time Ft is performed for the corresponding time and the initial duty set by the above The duty control signal is output to the driving means 30 and returned to the initial stage (S170).

(Fill time (Ft) = preset fill time (Ta) + maximum correction fill time (T3α))

The correction map stored in the memory of the shift control means 20 is represented as a table as follows.

However, in the case where the shift lever is not converted from the N range to the D range for the first time after starting the engine, the shift control means 20 measures the time the shift lever stays in the N range (S120).

The shift control means 20 that measures the time at which the shift lever stays in the N range determines whether the shift lever has been converted from the N range to the D range (S130).

When the shift lever is converted from the N range to the D range, the shift control means 20 sets the fill time correction value and the correction duty in the memory map according to the time that the shift lever measured in S120 stays in the N range. (S140).

Therefore, the shift control means 20 calculates and outputs the fill time Ft to be calculated by calculating the fill time correction t value set above by the set calculation formula to the preset fill time ta value (S150). ).

(Fill time (Ft) = preset fill time (Ta) + correction fill time (t))

By the fill time Ft output from the shift control means 20, the driving means 30 fills the oil in the flow path of the automatic transmission until the fill time ends.

In addition, the shift control means 20 calculates an initial duty value by calculating the correction duty value set in the 140 by a preset initial duty value Di and a set arithmetic expression, and when the fill type time ends, The duty control signal is outputted to the driving means 30 at the duty gradient and the duty output time set by the initial duty value calculated as described above and returned to the initial stage (S160).

(Initial Duty = Preset Initial Duty (Di) + Correction Duty)

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, when converting the first shift lever from the N range to the D range or the R range after starting the engine, the fill time and the initial duty value are set separately to improve the shift response delay and sense of shifting. In this case, the fill time correction value and the correction duty are selected according to the time stayed in the N range during shifting of the shift stage, and the fill time correction and duty correction are performed. A shift control method of an automatic transmission having an effect of reducing shift shock generated when driving after converting to a range or an R range and shifting to a D range after staying in the N range for more than a set time can be provided.

Claims (3)

Determining whether the shift lever is in the N range or the R range immediately after the driver starts the vehicle; Determining whether the shift lever is changed from the N range to the D range for the first time after starting the engine when the shift lever is in the N range or the P range; When the shift lever is changed from the N range to the D range for the first time after starting the engine, the maximum fill time T3α and the initial duty stored in the correction map of the memory are set separately, and the preset fill time Ta is set. And calculate the fill time (Ft) by calculating the maximum correction fill time (T3α) set by the set arithmetic formula to perform the fill time for the corresponding time and output the duty control signal by the initial duty set above. A shift control method of an automatic transmission, characterized in that the step consisting of. The method according to claim 1, Measuring a time for which the shift lever stays in the N range when the shift lever is not first converted from the N range to the D range after the engine is started; Determining whether the shift lever is converted from the N range to the D range; When the shift lever is converted from the N range to the D range, setting the fill time correction value and the correction duty in the memory map according to the measured time of the shift lever in the N range; Calculating and outputting a fill time (Ft) to be calculated and output by calculating a fill time correction (t) value set above by a preset fill time value (Ta); The initial duty value is calculated by calculating the correction duty value set above by a preset initial duty value Di and a set arithmetic expression, and when the fill time time outputted above is finished, the initial duty value calculated above is calculated. And outputting a duty control signal at a preset duty slope and a duty output time, and returning to an initial stage. (Fill time (Ft) = preset fill time (ta) + maximum correction fill time (t) Initial Duty = Preset Initial Duty (Di) + Corrected Duty) The method according to claim 2, And filling the oil into the corresponding flow path of the automatic transmission by the fill time (Ft) outputted from the above until the fill time ends.