KR100216056B1 - Shifting control method - Google Patents

Abstract

A step of sensing the number of revolutions of the engine in order to perform the shifting to the 3rd speed when the 2nd clutch is accelerated to increase the speed responsiveness by independently controlling the end clutch when the upshift control is performed from the 2nd speed to the 3rd speed, ,

Sensing an opening rate of the throttle valve,

Determining whether the driven state is a power on state or an off state after the above steps;

The step of releasing the oil pressure of the fourth speed platform by turning off the first and second solenoid valves for controlling the port conversion of the shift control valve when the power ON state is determined in the above step,

And independently controlling the end clutch by changing the duty ratios of the third and fourth solenoid valves for performing the port conversion of the first and second pressure control valves according to the rate of change of the turbine rpm with the lapse of the set time at the power-on A shift control method of an automatic transmission for a vehicle is provided.

Description

Shift control method of an automatic transmission for a vehicle

FIG. 1 is a view showing a hardware configuration of a shift control unit of a hydraulic control apparatus according to the present invention. FIG.

FIG. 2 is a hydraulic circuit diagram showing a hydraulic control system of a hydraulic control apparatus according to the present invention. FIG. 2 is a hydraulic circuit diagram showing a process of upshifting from 2 to 3 at power on or off.

3 is a flowchart for explaining a shift control operation of the hydraulic control apparatus according to the present invention;

FIG. 4 is a graph showing changes in turbine speed according to time when downshifting from the second speed to the third speed at the time of power-on.

5 is a graph showing on / off states of the first and second solenoid valves for controlling the shift control valve at power-on in the shift control method according to the present invention.

6 is a graph showing the duty ratios of the third and fourth solenoid valves controlling the pressure control valve at power-on in the shift control method according to the present invention.

Figure 7 is a hydraulic diagram of power-on.

FIGS. 8A and 8B are graphs showing the ON / OFF states of the first and second solenoid valves for controlling the shift control valve at power-off in the shift control method according to the present invention.

9 is a graph showing the duty ratios of the third and fourth solenoid valves controlling the pressure control valve at power-off in the shift control method according to the present invention.

Figure 10 is a hydraulic diagram of power off.

FIG. 11 is a view for explaining a process in which the conventional hydraulic control apparatus is shifted up from the second speed to the third speed.

The present invention relates to a shift control method for an automatic transmission for a vehicle, and more particularly, to a shift control method for a vehicular automatic transmission that includes an end clutch operating pressure operating in a third speed and a fourth speed in a power train requiring only two input elements in three speeds, Speed control of the three-speed synchronous machine in which the kick-down servo of the kick-down servo operates in conjunction with the releasing-side chamber pressure of the kick-down servo.

The automatic transmission includes a torque converter and a multi-stage transmission mechanism connected to the torque converter. The automatic transmission includes a hydraulic operation friction element for selecting one of the gear stages of the transmission mechanism according to the running state of the vehicle .

The hydraulic control system of the vehicular automatic transmission has a function of selecting the friction element through the control valve and operating the hydraulic pressure generated from the oil pump.

Such a hydraulic control system includes pressure control means for controlling the hydraulic pressure generated from the oil pump, manual and automatic transmission control means for forming a transmission mode, and transmission speed and responsiveness for forming a smooth transmission mode A damper clutch control means for operating a damper clutch of the torque converter, and a hydraulic pressure distributing means for distributing an appropriate hydraulic pressure supply to each friction element. The hydraulic control means controls the supply line pressure acting on the friction element, the torque converter supply pressure, the solenoid valve supply pressure, and the like, which substantially affects the transmission feeling.

To facilitate the understanding of the present invention, a process of downshifting from the fourth speed to the third speed in the conventional hydraulic control apparatus will be described with reference to FIG.

A torque converter 100 that receives power from the engine and converts the torque to transmit it to the transmission side; and an oil pump 102 that generates and discharges the oil necessary for the torque converter and the gear stage control.

A pressure regulating valve 106 which is generated from the oil pump 102 and which regulates the hydraulic pressure flowing along the conduit 104 to a constant pressure, a torque converter control valve (regulator) 106 for regulating the pressure of the torque converter and the lubricating oil 108), and a damper clutch control valve (110) for increasing the power transmission efficiency of the torque converter.

A part of the oil generated from the oil pump 102 is supplied to a reducing valve 112 for maintaining a lower pressure than the line pressure at all times and a manual switch for switching the oil passage while operating in conjunction with the position of the selector lever in the driver's seat And constitutes a flow path that can be supplied to the valve 114.

The constant hydraulic pressure reduced by the reducing valve 14 constitutes a flow path that can be used as a control pressure of a high-low pressure valve (not shown) that lowers the line pressure at the high-speed end and minimizes the drive loss of the oil pump And some of the cups are supplied to the pressure control valve 116 to constitute a flow path which can be used as the control pressure.

And a part of the hydraulic pressure supplied to the pressure control valve 116 is used to make a controllable pressure of the N-R control valve 118 which reduces the shift shock when the mode is changed from the neutral range to the reverse range.

A first solenoid valve 51 and a second solenoid valve 51 which are ON / OFF-controlled by a transmission control unit (TCU) are provided in a pipeline 120 through which hydraulic pressure flows when the manual valve 114 is in the running (D) And a shift control valve 12a for switching the oil passage by the action of the valve 52 is communicated to be supplied with the hydraulic pressure.

The pipeline 120 is connected to the first conduit 124 to supply the hydraulic pressure to the pressure control valve 116. The shift control valve 122 is connected to the second conduit 126, Speed line 128 and a fourth-speed line 130 are connected to each other to supply the control hydraulic pressure to the plurality of shift valves for controlling the respective speed change stages.

The second-speed line 126 is supplied to the left end port of the 1-2 shift valve 132 to control the valve, and the third-speed line 128 is connected to the 2-3 / 4-3 shift valve And the fourth speed line 130 is supplied to the left end port of the end clutch valve 136 and the rear clutch release valve 138 so that each valve can be controlled .

On the other hand, the pressure control valve 116 is configured such that the third solenoid valve 53 can switch the flow path, and the damper clutch control valve 110 is connected to the fourth solenoid valve S4 by the fourth solenoid valve S4, Can be switched.

The hydraulic pressure supplied to the pressure control valve 116 is controlled by the third solenoid valve 53 so that the ND control valve 122 reduces the shift shock when the selector lever is selected as the driving range (D) And a hydraulic pressure can be supplied to the rear clutch C 1, which is the first friction element, through the oil passage 140.

The rear clutch release valve 138 is provided in the oil passage connecting the ND control valve 140 and the rear clutch C1 so that the oil pressure can be supplied to the rear clutch or the supplied oil pressure can be discharged .

The oil pressure is supplied from the pressure control valve 116 to the kickdown servo C2, which is the second friction element acting as a reaction element at the second speed via the 1-2 shift valve 132.

Part of the hydraulic pressure via the 1-2 shift valve 132 passes through the 2-3 / 4-3 shift valve 134 and is transmitted to the front clutch C3, which is the third friction element acting as the third- And a part of the oil pressure controls the end clutch valve 136 so that the hydraulic pressure flowing to the third-speed channel 128 becomes the fourth And constitutes a flow path which can be supplied to the end clutch C4 which is a friction element.

When the manual valve 114 is in the reverse range, the hydraulic pressure supplied to the reverse first control line 142 is transmitted to the fifth friction element (not shown) acting as a reaction element at the reverse shift stage via the 1-2 shift valve 36 C5. The backward second control line 144 is connected to the manual valve 114 for operation of the third friction element C3 acting as an input element.

The second friction element C2 is provided with a kick-down switch 146 installed in the operating chamber to be turned off when hydraulic pressure is supplied to the operating chamber hi and to be turned on when supplied to the releasing chamber h2. So that the signal can be transmitted to the electronic control unit (TCU).

This hydraulic pressure unit is provided with three clutch means for transmitting rotational power by hydraulic pressure control, two brake means, and a shift planetary gear train having a complex planetary gear device employing a one-way clutch structurally rotatable only in one direction It is possible to perform the step control.

Since a known power train can be used, a description of the configuration of the power train will be omitted. However, what clutch means or brake means acts at each gear stage will be described.

Way clutch is restrained by the rear clutch C1 and the hydraulic pressure control in the running (D) range 1, and the one-way clutch restrains rotation in the direction opposite to the input. In the second speed, the rear clutch C1 transmits power, The rear clutch C1, the front clutch C3 and the end clutch C4 both act as input elements in the third speed and the kickback servo (third speed) C2) acts to realize the speed change stage control.

In the conventional hydraulic control apparatus thus constructed, when the upshift is made to the third speed in the second speed range of the traveling (D) range, the operation of the kickdown servo C2 is canceled in a state in which the rear clutch Cl is still operating The third solenoid valve 53 is duty-controlled to lower the hydraulic pressure supplied from the pressure control valve 116 to the operating-side chamber hi of the kick-down servo.

The valve spool of the 2-3 / 4-3 shift valve 134 is moved to the right as viewed in the drawing while the oil pressure is supplied from the shift control valve 122 to the third-speed channel 128 to operate the kick-down servo CB A part of the hydraulic pressure supplied to the side chamber is supplied to the front clutch C3 and the release side chamber hE of the kickdown servo.

When the third speed is completed in this state, the oil pressure of the third-speed channel is supplied to the end clutch C4 without any control.

However, the 2-3 upshift control of this method has a problem in that the operation of the end clutch is delayed when the lift foot-up control is performed from the second speed to the fourth speed since the end clutch is operated without control, thereby slowing down the shift response.

Further, there is a problem in that the structure of the end clutch valve 136 becomes complicated in order to operate the end clutch without control.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the conventional art as described above, and it is an object of the present invention to provide an engine control system that directly controls an end clutch when upshifting from a second speed to a third speed, Speed shift control method.

In order to realize the object of the present invention as described above, port conversion is performed by solenoid valves which are controlled on and off by a transmission control unit, and port conversion of shift valves for supplying or interrupting hydraulic pressure to / And a control pressure is supplied to each of the friction elements by duty control of the other solenoid valves at the time of shifting. In the shift control method for a vehicle automatic transmission, Sensing a rate of opening of the throttle valve; determining whether the driven state is a power on state or an off state after the steps; If it is determined that the first and second solenoid valves for controlling the port switching of the shift control valve are turned off, And changing the duty ratio of the third and fourth solenoid valves for performing the port conversion of the first and second pressure control valves in accordance with the rate of change of the turbine rpm with the lapse of the set time at the power-on, And a step of independently controlling the speed of the automatic transmission. Wherein when the power-off state is determined in the step of determining the driven state, the duty ratio of the pressure control solenoid valve is maximized at the time of shifting to keep the operating-side chamber pressure of the kickdown servo at the lowest state. ≪ / RTI >

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a control unit hardware according to the present invention. An input coil of a transmission control unit (TCU) is connected to an ignition coil Ic for detecting the number of revolutions of the engine. This ignition coil outputs two pulses per rotation to calculate the number of revolutions of the engine.

In addition, a throttle position sensor (TPS) is connected to another input terminal to sense the opening ratio of the throttle valve, and a pulse generator (Pg) is connected to another input terminal for sensing the rotation speed of the output shaft.

Further, a switch Ps for detecting the power-on-off is connected between the other applications of the transmission control unit (TCU).

The first solenoid valve S1 and the second solenoid valve S2 are electrically connected to the output terminal of the transmission control unit TCU to control the port switching of the shift control valve. A third solenoid valve 53 and a fourth solenoid valve 54 for controlling the port conversion are connected.

FIG. 2 shows a hydraulic control system according to the present invention in which the upshift from the second speed to the third speed is performed at power on. Before shifting to the third speed, the kick down servo C2 and the rear clutch (C1) is in operation.

The electronic control hydraulic control system is a system in which the solenoid valves, which are on / off-controlled or duty-controlled by a transmission control unit (TCU) receiving a throttle valve opening signal and a vehicle speed signal, .

Such a hydraulic control system includes a torque converter 2 that receives power from an engine and converts the torque to transmit it to the transmission side, an oil pump 4 for generating and discharging oil necessary for the torque converter and the gear- ).

A pressure regulating valve 8 which is generated from the oil pump 4 and makes the pressure of the oil flowing along the duct 6 constant, a torque converter control valve 10 which constantly regulates the pressure of the torque converter and the lubricating oil And a damper clutch control valve 12 for increasing the power transmission efficiency of the torque converter.

A part of the oil generated from the oil pump 4 is supplied to a reducing valve 14 for maintaining the pressure lower than the line pressure at all times and a manual valve for switching the oil passage while operating in conjunction with the position of the selector lever And constitutes a flow path which can be supplied to the valve 16.

The constant hydraulic pressure reduced by the reducing valve 14 constitutes a flow path that can be used as the control pressure of the high-low pressure valve 18 which lowers the line pressure at the high-speed end and minimizes the drive loss of the oil pump And a part of the hydraulic pressure is supplied to the first pressure control valve 20 and the second pressure control valve 22 to constitute a flow path which can be used as the control pressure.

A part of the hydraulic pressure supplied to the first and second pressure control valves makes a flow path that can be used for the control pressure of the N-R control valve 24, which reduces a shift shock when the mode is changed from the neutral range to the reverse range.

The first solenoid valve S1 and the second solenoid valve S2 (not shown), which are on / off-controlled by the transmission control unit, are connected to the line 26 through which hydraulic pressure flows when the manual valve 16 is in the running (D) The shift control valve 28 for switching the oil passage is communicated to be supplied with the hydraulic pressure.

The second shift control valve 28 is connected to the second speed line 30, the third speed line 32 and the fourth speed line 34 to supply the control hydraulic pressure to the plurality of shift valves for controlling the respective speed change stages .

That is, the second-speed conduit 30 is supplied to the left end port of the 1-2 shift valve 36 to control the valve, and the third-speed conduit 32 is connected to the 2-3 / 4-3 shift valve And the fourth-speed line 34 is connected to the right-hand end port of the 2-3 / 4-3 shift valve 38 and the 2-4 / 3- 4 shift valve 40 and the left end port of the end clutch valve 42 so as to control each valve.

Meanwhile, the first pressure control valve 20 is configured so that the third solenoid valve S3 can switch the flow path, and the second pressure control valve 22 is configured to be switched by the fourth solenoid valve S4 So that the flow path can be switched.

The first conduit 44 is branched from the manual valve 16 and supplied to the first pressure control valve 20 and the second pressure control valve 22 so that the third and fourth solenoid valves S3 and S4 via the 2-4 / 3-4 shift valve 40 to the first friction element C1, which is the first-speed input element.

The first pressure control valve 20 constitutes a flow path through which the hydraulic pressure can be supplied to the second friction element C2 acting as a reaction force element at the second speed via the 1-2 shift valve 36.

Further, a part of the hydraulic pressure via the 1-2 shift valve 36 passes through the 2-3 / 4-3 shift valve 38 and is transmitted via the end clutch valve 42 to the end And the hydraulic pressure supplied to the end clutch C4 is configured to be supplied to the port 46 of the accumulator 43. The hydraulic pressure supplied to the end clutch C4 can be supplied to the port 46 of the accumulator 43. [

The hydraulic pressure supplied to the reverse first control line 50 when the manual valve 16 is in the reverse range is transmitted to the low / reverse brake C5. The backward second control line 52 is connected to the manual valve 16 for the operation of the front clutch C3 which functions as an input element.

The backward second control line 52 is provided with a check valve 53 to delay the release of the hydraulic pressure when releasing the operating hydraulic pressure, thereby improving the shifting feeling.

The kick-down servo C2 described above is provided with a kick-down switch 54 in the operating chamber to be turned off when hydraulic pressure is supplied to the operating chamber h1, and is turned on when supplied to the releasing chamber h2. And to transmit the signal to the electronic control unit (TCU) while being controlled.

In the figure, reference numeral S5 denotes a solenoid valve for controlling the damper clutch control valve.

The hydraulic control apparatus includes three clutch means for transmitting rotational power by hydraulic pressure control, two brake means, and a shift planetary gear train having a complex planetary gear device employing a one-way clutch structurally rotatable only in one direction It is possible to perform the step control.

Since a known power train can be used, a description of the configuration of the power train will be omitted. However, what clutch means or brake means acts at each gear stage will be described.

Way clutch is restrained by the rear clutch C1 and the oil pressure control in the running (D) range 1 and the one-way clutch restrains rotation in the direction opposite to the input. In the second speed, the rear clutch C1 transmits power, Both of the rear clutch C1 and the end clutch C4 act as an input element to rotate the gear train 1: 1 in the third speed and the front clutch C3 and the fourth clutch The kick-down servo C2 acts to realize the speed change stage control.

In the hydraulic control apparatus of the present invention thus constructed, the following control is performed when upshifting to the third speed in the second speed is required.

That is, first, when the opening ratio of the throttle valve increases and the vehicle speed becomes faster in the power running state (D) range second speed state, the transmission control unit completes the third speed control through the control as shown in FIG. .

That is, when the control for shifting is started, the transmission control unit TCU reads the signal transmitted through the ignition coil Ic in step S10 to sense the number of revolutions of the engine.

Subsequently, in step S12, the signal transmitted from the throttle position sensor TPS is read to determine the opening ratio of the throttle valve, and in step S14, it is determined whether or not the power is on.

When the driven condition is detected in the power-on state in the step S14, the transmission control flag is set such that even if the first solenoid valve S1 is controlled from the ON state to the OFF state, the second solenoid valve S2 is continuously operated Off state, and the port of the shift control valve 28 is switched in FIG. 2. (Step S16)

After setting the initial duty ratio of the third solenoid valve S3 at the power-on in step S18, the duty ratio of the third solenoid valve 53 is changed in accordance with the time change in the power-on in the next step S20 . The first and second solenoid valves S1 and S2 perform the control as shown in FIGS. 5A and 5B, and the third and fourth solenoid valves S3 and S4 perform the control shown in FIG. 6A, , b). At this time, the third solenoid valve is controlled in such a state that the duty ratio is gradually increased after the start of the shift, and when the duty ratio is controlled to the highest, the feedback control is performed.

By this control, the hydraulic pressure is supplied to the third-speed pipeline 32 to move the valve spool of the 2-3 / 4-3 shift valve 38 to the right as viewed in the figure, so that the hydraulic pressure Side chamber h2 of the kick-down servo C2 via the 1-2 shift valve 36 and the 2-3 / 4-3 shift valve 38 as well as a part of the hydraulic pressure is supplied to the end clutch valve 42 to the accumulator 43 and the end clutch C4 to show the hydraulic pressure diagram as shown in Fig.

In other words, in the third speed, the rear clutch C1 and the end clutch C4 act as input elements. At this time, it is realized that the end clutch is directly supplied to the control pressure and a part of the hydraulic pressure is absorbed by the accumulator, .

If such control is performed, if the operation of the rear clutch and the kick-down servo is released in step S22, the completion of the shift control is determined by determining the completion of the synchronization in step S24.

If it is determined in step S14 that the driven condition is determined to be the power-off state, in step S16-1, the transmission control unit controls the first solenoid valve S1 from the on state to the off state, The solenoid valve S2 is continuously controlled to be in the OFF state to perform the port conversion of the shift control valve B8 in the second diagram.

In step S18-1, the initial duty ratio of the third solenoid valve S3 is set during the power-off. Then, in the next step S20-1, the third solenoid valve S3 according to the time- Thereby changing the duty ratio of the battery.

In other words, the first and second solenoid valves S1 and S2 perform control as shown in FIG. 8 (a) and (b), and the third and fourth solenoid valves S3 and S4 perform control as shown in FIG. 9 ). At this time, the third solenoid valve is controlled at the highest duty ratio after the start of the shift, and the feedback control is performed.

By this control, the hydraulic pressure is supplied to the third-speed pipeline 32 to move the valve spool of the 2-3 / 4-3 shift valve 38 to the right as viewed in the figure, so that the hydraulic pressure Side chamber h2 of the kick-down servo C2 via the 1-2 shift valve 36 and the 2-3 / 4-3 shift valve 38 as well as a part of the hydraulic pressure is supplied to the end clutch valve 42 to the accumulator 43 and the end clutch C4, the oil pressure line as shown in FIG. 10 is obtained.

In other words, in the third speed, the rear clutch C1 and the end clutch C4 act as input elements. At this time, it is realized that the end clutch is directly supplied to the control pressure and a part of the hydraulic pressure is absorbed by the accumulator. 10, the operating chamber pressure of the kick-down servo C2 is lower than that in the power-on state at the time of power-off, and the hydraulic pressure for actuating the end clutch Is maintained at a pressure lower than that at the time of power-on, and can be increased to increase the driving force.

As described above, the shift control method according to the present invention can control the end clutch and the releasing chamber pressure of the kickdown servo by communicating with each other, thereby preventing the engine from running up when the lift foot-up is performed from the second speed to the fourth speed. The configuration of the end clutch valve can be simplified and switching of the end clutch pressure at the time of shifting from the third speed to the fourth speed or from the fourth speed to the third speed makes it possible to perform safe control even when the spring and the valve spool are stuck , The hydraulic pressure can be temporarily stored in the accumulator when shifting from the second speed to the third speed, thereby reducing the shift shock.

Claims (3)

The port conversion is performed by the solenoid valves which are controlled by the transmission control unit to be switched on and off so that the port conversion of the shift valves for supplying or cutting off the hydraulic pressure to the respective friction elements is performed and the other solenoid valves are duty- A shift control method of a vehicular automatic transmission in which a control pressure is idled by respective friction elements, comprising the steps of: sensing a revolution speed of an engine to perform shifting to a third speed in the case of acceleration during a second speed running; The method comprising the steps of: sensing a rate of change of a vehicle speed; determining a driving state of the vehicle (power on or power off) after the steps; and controlling the hydraulic pressure according to the state of the vehicle determined in the step A shift control method for an automatic transmission. The vehicle automatic control system according to claim 1, wherein, in the step of determining the driven state, when the power-off state is determined, the duty ratio of the pressure control solenoid valve is maximized at the time of shifting to maintain the operating chamber pressure of the kick- A method of controlling a shift of a transmission. 2. The method according to claim 1, further comprising the steps of: turning off the first and second solenoid valves for controlling the port switching of the shift control valve to release the oil pressure of the fourth speed channel when the power on state is determined; Changing the duty ratio of the third and fourth solenoid valves for performing the port conversion of the first and second pressure control valves in accordance with the rate of change of the turbine rpm so as to independently control the end clutch.