KR20040043521A - Method of controlling shift for a automatic transmission - Google Patents

Abstract

PURPOSE: A shift control method of an automatic transmission for a vehicle is provided to minimize the delay for starting to shift by shifting after returning line pressure to maximum pressure before deciding the shift by pre-reading a shift pattern line in variable-controlling the line pressure. CONSTITUTION: In a shift control method of an automatic transmission for a vehicle, a line pressure return control method is composed of steps for deciding if a present vehicle is in a pre-reading region in detecting control operations from a transmission in traveling(S100); controlling the return of the line pressure and then deciding if the control operation is for shift control or damper clutch control(S120,S130); finishing the step if not the shift control and the damper clutch control and deciding that the line pressure is returned if the shift control and the damper clutch control; controlling the return of the line pressure and then computing a delaying time corresponding to plural control conditions if the line pressure is not returned and directly computing the delaying time corresponding to the control conditions if the line pressure is returned(S160,S170); and controlling the shift for the computed delaying time, keeping the maximum line pressure for constant time, and then finishing the process.

Description

Shift control method of automatic transmission for vehicles {METHOD OF CONTROLLING SHIFT FOR A AUTOMATIC TRANSMISSION}

The present invention relates to a shift control method for an automatic transmission for a vehicle. More particularly, the line pressure is reduced by pre-shifting the shift pattern line during the line pressure variable control so that the line pressure return waiting time is performed before the shift determination. The present invention relates to a shift control method of an automatic transmission for a vehicle in which shifting is performed after returning to maximum pressure to minimize shift delay and improve shift control responsiveness.

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

In other words, when the driver converts the select lever to the desired shift stage, the manual valve port of the hydraulic control system is changed, and the hydraulic pressure supplied from the oil pump is controlled by the transmission gear mechanism (power train) according to the duty control of the solenoid valve. Shifting is achieved by selectively operating the elements (clutch and brake).

Accordingly, the automatic transmission has a great influence on the shifting performance and the shifting feeling depending on how the hydraulic control system that operates the power train is configured and controlled. In the case of the line pressure of the hydraulic control system, it is a source of hydraulic pressure. Therefore the optimum line pressure must be supplied.

In controlling the line pressure of such a hydraulic control system, when shift control is performed in the process of variablely controlling the line pressure, the line pressure must return to the maximum pressure (original pressure). As the pressure was returned to the maximum pressure, a delay time was always generated, and it was common to perform a control to delay the shift by the line pressure return delay time in order to secure the shift feeling according to the delay.

However, when the shift is delayed by the line pressure return delay time as described above, the passenger may easily feel that the shift is delayed, and in particular, the shift feeling is decreased due to the change in the torque of the engine during the shift delay time. It is implicated.

Therefore, the present invention has been invented to solve the above-mentioned conventional problems, and an object of the present invention is to read the shift pattern line in advance during the line pressure variable control to make the line pressure return waiting time before the shift determination. In addition, the present invention provides a shift control method for an automatic transmission for a vehicle in which shifting is performed after returning the line pressure to the maximum pressure, thereby minimizing a delay of shift start and improving shift control responsiveness.

1 is a block diagram of an engine total system for operating the present invention.

2 is a shift pattern diagram for explaining a control concept of the present invention.

3 is a flow chart according to the present invention.

In order to realize this, the present invention provides a vehicle automatic transmission in which a change is made while the vehicle speed and the throttle opening angle are shifted while passing through a shift line dividing each shift stage.

Each read-out line is set to the offset portion of the upshift line and the down-shift part of each downshift line at each shift stage, and the upshift and downshift readout area is respectively between the upshift line and the readout line, the downshift line and the readout line. When the throttle opening degree and the vehicle speed state enter this read range, the shift control is performed after the return control is performed at the maximum line pressure.

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

FIG. 1 is a block diagram of a total control system capable of totally controlling an engine and an automatic transmission. When a driving state of a current vehicle is input to the ECU 20 from various sensors forming the engine control detection unit 10, FIG. The ECU 20 controls the engine control driver 30 by controlling the engine control driver 30 by comparing the information with the data which has been input in advance.

At the same time, the ECU 20 transmits information to the transmission control unit 40 (hereinafter referred to as TCU) if the information necessary for shift control is performed so that the shift control is performed. In this case, the information transmitted from the ECU 20 is transmitted from the ECU 20. And by comparing the information input from the shift control detecting unit 50 with the previously input data and controlling the shift control driver 60 and the line pressure control unit 70, the optimum shift control is achieved.

The engine control detection unit 10 is, as is known, all information necessary for engine control such as a vehicle speed sensor, a crank angle sensor, an engine speed sensor, a coolant temperature sensor, a turbine speed sensor, a throttle position sensor, and the like. The shift control detecting unit 50 refers to sensors that provide all information necessary for shift control such as an input / output speed sensor, an oil temperature sensor, an inhibitor switch, a brake switch, and the like.

In addition, the engine control driving unit 30 means all driving units for engine control, and the shift control driving unit 60 means all solenoid valves applied to the hydraulic control means of the automatic transmission.

In addition, the line pressure control unit 70 controls the line pressure by duty control of the solenoid valve for the regulator valve controlled by the transmission control unit (TCU), thereby minimizing fuel consumption and driving loss due to unnecessary oil pump load. The control that can be done is made.

There are various ways to send information from the ECU 20 to the TCU 40, but one example is CAN communication.

The CAN communication is a multi-communication of data through a CAN bus line, and can transmit and receive all necessary information to each controller. If additional information is required for a controller, only CAN software can be changed without changing hardware.

2 is a shift control pattern diagram for explaining the line pressure control concept of the present invention. In the present invention, the line pressure is shifted by reading before the upshift line when upshifting, and before the downshift line when downshifting. It is a concept to control the return to maximum pressure beforehand.

More specifically, on the left side of each upshift line (1 → 2) (2 → 3) (3 → 4) (4 → 5) (5 → 6) in the upshift for each shift stage based on the shift pattern line. In the downshift mode, the first line is offset from the number of times to the right of each downshift line (1 ← 2) (3 ← 2) (4 ← 3) (5 ← 4) (6 ← 5). Set U1, U2, U3, U4, U5, D1, D2, D3, D4, D5, and set the area surrounded by the reading line with each shift line. UZ1) (UZ2) (UZ3) (UZ4) (UZ5), (DZ1) (DZ2) (DZ3) (DZ4) (DZ5) and return to maximum line pressure when the throttle and vehicle speed conditions enter this read range. Will be done.

That is, when the throttle and the vehicle speed state enter the read area UZ1, UZ2, UZ3, UZ4, UZ5 of the upshift in the upshift process, the line pressure is controlled to the maximum pressure, and the throttle of the downshift process is performed. And when the vehicle speed state enters the readout areas DZ1, DZ2, DZ3, DZ4, and DZ5 of the downshift.

In the line pressure control process as described above, the actual shift is shift pattern lines (1 → 2) (2 → 3) (3 → 4) (4 → 5) (5 → 6), (1 ← 2) (3 ← 2) Since it starts when it crosses (4 ← 3) (5 ← 4) (6 ← 5), shift control is not necessarily performed even if it enters a precedent area.

The offset amount is set so that the shift start delay is small in the throttle direction of the shift pattern line, the vehicle speed, and the area in which the line pressure variable control can be widened.

To this end, first, the response delay tp of the line pressure is obtained, which is assumed to be approximately 200 msec.

The maximum acceleration (ΔV / Δt) of the vehicle is calculated and calculated, and the offset line is set by multiplying the response delay (tp). For example, if the maximum acceleration (ΔV / Δt) is 20 Km / h / sec. Multiplying this by 200msec results in 4Km / h, but it is preferable to set it to 5Km / h in consideration of the margin.

In view of this, the shift delay is unnecessary when the throttle is opened at constant speed.

In addition, the throttle direction takes about 0.1 to 0.2 msec when a person presses the accelerator pedal from 0 to 100%, and it is impossible to completely eliminate the delay during lift put-up and kick-down because the accelerator pedal is pressed less than the return time. With this in mind, it is desirable to set the offset line under various conditions in the shift pattern line and compare the area of the line pressure variable control with the area of the maximum line pressure. In this case, when the throttle change is made slowly at 5% / 200 msec, the shift delay is unnecessary.

In addition, it is preferable to set the offset in which the read range is wider than the inner side of the offset line obtained as the read line.

As described above, in order to perform the shift control after returning the line pressure to the maximum pressure, the shift control can only be delayed until the line pressure reaches the maximum pressure. Although the throttle correction can be performed with respect to the current of the VFS (variable solenoid valve), in many cases, delay avoidance at the start of shifting cannot be avoided.

As described above, the detailed operation flow for the control of the line pressure is performed as shown in FIG. 3. First, when it is determined that the control by the shift control or the damper clutch control is performed while the vehicle is running, the current vehicle is read in advance. It is determined whether the area (S100).

If it is determined in step S100 that the read-out area is determined, the line pressure is returned (S110), and after performing the line pressure return control to make a more accurate return (S120), whether the control operation is shift control or damper clutch control. It is determined (S130).

If it is determined in step S100 that it is not the read area, it is recognized that line pressure is not returned (S111), and the process proceeds to step S130.

If it is determined in step S130 whether the shift control or the damper clutch control is satisfied, it is determined whether the line pressure return has not been made (S140), and if the line pressure return has not been performed, after performing the line pressure return control ( In step S150, the delay time TD according to the request control is calculated (S160), and the shift control according to the shift control condition is performed (S170).

The line pressure return in steps S110 and S150 consists of 10.5 kgf, which is the maximum line pressure at speeds 1 and 2, and 8.5 kgf, which is the maximum line pressure at speeds 3 to 6.

If it is determined in step S150 that the line pressure return is made, the process directly enters step S160 to calculate the delay time according to the request control, and then shift control is performed in step S170.

The control condition in the step S160 is a control element that can be generated in the transmission. In the present invention, the parameter of the condition is damper clutch control, an up shift in the power on state, an up shift in the power off state, and a power on state. The five shift conditions, such as down-shifting and down-shifting in the power-off state, allow the respective delay times to be calculated.

More specifically, when the control is started through the steps S140 and S150, it is first determined whether the damper clutch control (S161A), when the damper clutch control is made, after calculating the delay time according to the damper clutch control (S161B) step S170 In step S161A, if it is determined that the damper clutch is not controlled, it is determined whether an upshift in the power-on state is performed (S162A).

If the condition is satisfied in the step S162A, the delay time for each shift stage with respect to the upshift in the power-on state is calculated (S162B) to perform the shift control accordingly, and if the condition in the step S162A is not satisfied, the power is It is determined whether the shift is the upshift in the off state (S163A).

If the condition is satisfied in the step S163A, the delay time for each shift stage with respect to the upshift in the power-off state is calculated (S163B) to perform the shift control accordingly, and if the condition in the step S163A is not satisfied, the power is It is determined whether it is a downshift in the on state (S164A).

If the condition is satisfied in the step S164A, the delay time for each shift stage for the downshift in the power-on state is calculated (S164B), so that the shift control is performed accordingly, and if the condition in the step S164A is not satisfied, It is determined whether the shift is the down shift in the power-off state (S165A).

If the condition is satisfied in the step S165A, the delay time for each shift stage with respect to the downshift in the power-off state is calculated (S165B) so that the shift control is performed accordingly, and ends if the condition in the step S165A is not satisfied. .

After the shift control is calculated by calculating the delay time according to each control condition, the maximum line pressure is held (S180), and when the reference time elapses in this state, the normal shift control is performed.

In the control process as described above, the delay time in steps S161B, S162B, S163B, S164B, and S165B is calculated by one or each gear stage according to the characteristics of each control condition, and shift control is performed after the delay time has elapsed. will be.

As described above, according to the present invention, the shift pattern line is pre-readed during the line pressure variable control in advance so that the shift is performed after the line pressure is returned to the maximum pressure before the shift judgment, thereby minimizing the delay of the shift start. It is an invention that can improve the shift control response.

Claims (6)

In an automatic transmission for a vehicle in which a shift is made while a vehicle speed and a throttle opening angle change while passing through a shift line that partitions each shift stage, Each of the upshift lines and the upshift line, the downshift line, and the readout line are respectively set up in the offset portion of the upshift line and the downshift line of each downshift line at each shift stage. When the throttle opening degree and the vehicle speed state enter the pre-reading region, the shift control is performed after the return control is performed at the maximum line pressure. The shift control method of claim 1, wherein the amount of offset is set to a value obtained by multiplying the maximum acceleration (ΔV / Δt) of the vehicle by the response delay time of the line pressure. The method of claim 1, wherein the line pressure return control comprises: a first step of determining whether the current vehicle is a read ahead area when any control is detected in the transmission while the vehicle is running; A second step of determining whether the control operation is shift control or damper clutch control after performing the line pressure return control if it is determined that the read-out area is the first step; Terminating if it is determined that the shift control and the damper clutch control are not performed in the second step, and determining whether the line pressure return has been made if the shift and damper clutch control is determined; If it is determined in the third step that the line pressure recovery has not been performed, after performing the line pressure recovery control, the delay time corresponding to the plurality of control conditions is calculated, and if the line pressure recovery has been made, Calculating a delay time; A shift control method is performed after the delay time calculated in the fourth step has elapsed. The shift control method of the automatic transmission for a vehicle is performed in a fifth step of maintaining the maximum line pressure after a predetermined time. 4. The shift control method for an automatic transmission for a vehicle according to claim 3, wherein the line pressure return is returned at high speeds at 1 and 2 speeds and relatively low at high speed shift speeds of at least 3 speeds. 4. The control condition in the fourth step is a damper clutch control, an up shift in a power on state, an up shift in a power off state, a down shift in a power on state, a down shift in a power off state. Shift control method for an automatic transmission for a vehicle, characterized in that set in five control conditions. The method of claim 3 or 5, wherein the delay time for the control condition in the fourth step, Determining a damper clutch control and calculating a delay time according to damper clutch control when damper clutch control is performed; If it is determined that the damper clutch control is not performed in the first step, determining whether the upshift in the power-on state is satisfied, and calculating a delay time for each shift stage with respect to the upshift in the power-on state when the condition is satisfied; A third step of calculating a delay time for each shift stage with respect to an upshift in a power-off state if it is determined that the upshift in the power-off state is not satisfied if the determination condition in the second step is not satisfied; ; If it is not satisfied that the determination condition of the third step is satisfied, determining whether it is a downshift in the power-on state and, if the condition is satisfied, calculating a delay time for each shift stage with respect to the downshift in the power-on state; If it is not satisfied that the determination condition of the fourth step is determined, it is determined whether the downshift in the power-off state is satisfied. Shift control method of an automatic transmission for a vehicle, characterized in that.