KR100305855B1 - Methode for controlling shift automatic transmission of vehicle - Google Patents

Abstract

To improve the riding performance by minimizing the occurrence of abnormal vibration occurring at the end of the shift when the 'D' range 4 → 2 is skipped;

When the shift signal from the 4th speed to the 2nd speed is input, the first shift control solenoid valve is turned off immediately after the shift start detection, and the second shift control solenoid valve is kept off for a predetermined time after the shift start. State controlled, the third shift control solenoid valve is continuously on, and the first and second pressure control solenoid valves are 4-2 down skipped while the duty is controlled,

The first pressure control solenoid valve PCSC-A determines whether the current shift process is the power-off 4-2 control in the power-on manual shift 4-2 state while the duty is controlled to 100% before synchronization is completed. If it is determined that the duty is maintained at 100% for the Thold after controlling to 0%, if not determined to control the shift to 0% to provide a shift control method for 4-2 down skip of the automatic transmission for a vehicle. do.

Description

TECHNICAL FOR CONTROLLING SHIFT AUTOMATIC TRANSMISSION OF VEHICLE}

The present invention relates to a shift control method for 4-2 down skip of an automatic transmission for a vehicle, and more particularly, to minimize abnormal vibration occurring at the end of the shift when the 'D' range 4 → 2 down skips. It relates to a shift control method.

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

In other words, when the driver changes the select lever to the desired gear range, the manual valve port is changed and the hydraulic pressure supplied from the oil pump is selectively operated according to the duty control of the solenoid valve. Let this be done.

The automatic transmission operated according to this operating principle has a friction element that is deactivated in the operating state when the shift to the target shift stage is performed, and a friction element that is converted from the deactivation state to the operating state. Since the shift performance of the automatic transmission is determined according to the timing of deactivation and start of operation of these friction elements, recent studies on shift control methods for better shift performance have been actively conducted.

In view of the technical background of the present invention, the shift control of the automatic transmission according to the driving state of the vehicle upshift shift control in which the shift is sequentially made from the 1st speed, which is the full speed, to 4th speed, and 1 from the 4th forward speed. There are downshift shifting control in which shifting is sequentially performed up to a second speed, and downskip shifting control in which downshifting is performed from 4th speed to 2nd speed, 3rd speed to 1st speed, and the like. Related to.

In other words, if you want to skip the vehicle driving at the fourth speed down to the second speed, the end clutch of the kick-down servo and the end clutch operating at the fourth speed can be released and the rear clutch can be operated. The end clutch pressure is conventionally controlled to maintain the second clutch sync point.

However, when the end clutch pressure is maintained up to the second speed synchronizing point during the 4 to 2 down skip shift as described above, the end clutch is not released while the operating pressure is supplied to the rear clutch, thereby causing abnormal vibration. There arises a problem that it produces | generates and reduces shift performance and a ride comfort.

Therefore, the present invention has been invented to solve the above problems, an object of the present invention by improving the shifting performance by minimizing the occurrence of abnormal vibration (Judder) generated at the end of the shift when the 'D' range 4 → 2 down skip In addition, the present invention provides a shift control method at the time of skipping 4-2 of an automatic transmission to improve riding comfort.

1 is a block diagram of an automatic transmission to which the present invention is applied.

2 is a block diagram of a hydraulic control system to which the present invention is applied.

Figure 3 is a duty pattern diagram at 4 → 2 shift in accordance with the present invention.

Figure 4 is an operation flowchart of the first pressure control valve applied to the present invention.

5 is an operation flowchart of a second pressure control valve applied to the present invention.

In order to realize this, in the present invention, when the shift signal from the fourth speed to the second speed is input, the first shift control solenoid valve (SCSV-A) is turned off immediately after the shift start detection, and the second shift control solenoid valve (SCSV) -B) is maintained in the off state for a predetermined time (t1) after the start of the shift is controlled to the on state, the third shift control solenoid valve (SCSV-C) is continuously on, and the first, second Pressure control solenoid valves (PCSV-A, B) are duty controlled with 4-2 down skip

When the first pressure control solenoid valve (PCSC-A) enters the 4-2 shift stage, the pressure release time t _o of the end clutch and the travel time and fill time of the spool-B of the rear clutch release valve are Determining a control condition that satisfies the present condition by comparing the condition, controlling the duty from 0% to D _A1 , and then controlling the duty with an α1 slope;

Controlling the tilt of α1 to D _A2 in the above step and maintaining the state until the synchronization is detected, and increasing the duty to 100% when the synchronization is detected;

In the above step, it is determined whether the current shift process is the power-off 4-2 control in the power-on manual shift 4-2 state. ;

In the above step, if it is determined that the current shift process is not the power-off 4-2 control in the power-on manual shift 4-2 state, 4-2 down skip of the automatic transmission for a vehicle is performed by controlling the duty to 0% to complete the shift. It is characterized by providing a shift control method of the city.

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

1 is a configuration diagram of a shift control apparatus to which the control method of the present invention is applied, wherein the shift control apparatus is a rotational speed of a turbine on an output side when a rotational power is output by torque conversion from the engine 10 through the torque converter 20. Is detected and input to the shift control unit 30, the overall state such as the vehicle speed, the throttle opening rate, and the temperature of the transmission is detected from the driving state detection unit 40, and the corresponding electrical signal is input to the shift control unit 30. do.

Then, the shift control unit 30 determines the overall driving state of the vehicle based on the signal applied from the driving state detecting unit 40, and outputs a duty pattern signal for hydraulic control based on the data of the set map table. Will drive (50).

The hydraulic system 50 controls each friction element by driving each solenoid valve for shift stage synchronization according to a control signal applied from the shift control unit 30, thereby controlling the opening rate and vehicle speed and torque converter of the throttle valve. According to the turbine rotational speed in the target shift stage is to perform the up shift or down shift.

Figure 2 shows an example of the hydraulic control system to which the present invention is applied, looking at its hydraulic system configuration, the torque converter 102 to convert the torque received from the engine to the torque transmission to the transmission side, and the torque converter and the gear stage It includes an oil pump 104 for generating and discharging the oil required for control and the oil required for lubrication.

In the pipeline 106 through which the hydraulic pressure generated from the oil pump 104 flows, a pressure regulating valve 108 for making the oil flowing along the pipeline to a constant pressure, and a torque for constantly adjusting the pressure of the torque converter and the lubricating oil. The converter control valve 110 and the damper clutch control valve 112 for increasing the power transmission efficiency of the torque converter are connected.

And some of the oil produced from the oil pump 104, the reducing valve 114 to maintain the pressure at all times lower than the line pressure, and a manual valve for switching the flow path while interlocking depending on the position of the selector lever in the driver's seat The constant hydraulic pressure supplied to 116 and depressurized by the reducing valve 114 is supplied to the first pressure control valve 118 and the second pressure control valve 120 to be used as the shift stage control pressure.

A part of the hydraulic pressure supplied to the first and second pressure control valves 118 and 120 is supplied to the NR control valve 122 which reduces shift shock when the mode is changed from the neutral range to the reverse range, and the manual valve ( The first shift control solenoid valve (SCSV-A) and the second shift control solenoid valve, which are controlled on / off by the transmission control unit, to the pipeline 124 through which hydraulic pressure flows when the 116 is in the travel (D) range. The shift control valve 126 which switches the flow path by the action of SCSV-B is connected, and manual and automatic shift control is performed with the manual valve 116 mentioned above.

In addition, the shift control valve 126 is connected to the 2nd speed line 128, the 3rd speed line 130, and the 4th speed line 132, and the 1st speed line 134 is branched on the said line 124, Line pressure is supplied to the first and second pressure control valves 118 and 120, and the first and second pressure control valves 118 and 120 are first and second pressure control solenoid valves (PCSV-A) (PCSV-). The flow path is switched by B) so that the first pressure control valve 118 supplies the control pressure to the friction element during the shift control, and the second pressure control valve 120 acts as an input element of the first speed stage. ) To drive pressure.

The second speed conduit 128 of the shift control valve 126 is supplied to the left end port of the 1-2 shift valve 136 to control the valve, and the third speed conduit 130 includes two conduits 138 ( Branched to 140, the first branch pipe 138 is supplied to the left end port of the 2-3 / 4-3 shift valve 142 to control the valve, the second branch pipe 140 is The distal end is branched to supply hydraulic pressure to the end clutch valve 145 and the high low pressure valve 146.

In addition, the four-speed pipeline 132 is in communication with the left end port of the rear clutch release valve 148 and the right end of the 2-3 / 4-3 shift valve 142 to control these valves, a part of the hydraulic distribution means The fail-safe function is the most ideal gearshift stage when a stick phenomenon occurs between the valve and at least two friction elements, the inability of the transmission control unit (hereinafter referred to as TCU) or the respective valves forming the hydraulic distribution means. The fail-safe valve 150 is disposed as a safety means to perform the operation.

A timing control conduit 152 is connected to the manual valve 116 and uses hydraulic pressure flowing along the conduit as a control pressure of the control switch valve 144, and is disposed on the timing control conduit 152. Controlled by a shift control solenoid valve (SCSV-C).

And when the manual valve 116 is in the reverse (R) range, the hydraulic pressure supplied to the reverse first control conduit 154 is passed through the rear clutch release valve 148 and the 2-3 / 4-3 shift valve 142. The low-reverse acting as a reaction element at the reverse shift stage through the 1-2 shift valve 136 while allowing the hydraulic pressure to be supplied to the front clutch C4 and to the reverse second control conduit 156. The hydraulic pressure is supplied to the brake C5, and a part of the hydraulic pressure supplied to the front clutch C4 can be simultaneously supplied to the release side chamber h2 of the kick-down servo C2.

In addition, the end clutch valve 160 which can be controlled by the end clutch C3 operating pressure on the second branch conduit 140 of the three-speed conduit 130 supplying the three-speed pressure to the control switch valve 144. Was placed.

The control switch valve 144 is controlled by the third shift control solenoid valve (SCSV-C) while kicking down the second speed line 128 of the shift control valve 126 at 2, 3, and 4 speeds. The actuating side chamber of the kick-down servo C2 is supplied to the actuating side chamber h1 of (C2) and supplied with the control pressure of the first pressure control valve 118 via the 1-2 shift valve 136. (h1) or the end clutch C3.

With this configuration, the rear clutch C1 operates at the first forward speed, the rear clutch C1 and the kick-down servo C2 operate at the second speed, and the rear clutch C1, the end clutch C3, And the front clutch (C4) is operated, the shift is made while the kick-down servo (C2) and the end clutch (C3) in the fourth speed.

In such a hydraulic control system, when downshifting from the 4th speed to the 2nd speed, it is controlled by the duty pattern as shown in FIG. 3. When the shift signal from the 4th speed to the 2nd speed is input, a 1st shift control solenoid valve ( SCSV-A is turned off immediately after the shift start detection, and the second shift control solenoid valve (SCSV-B) is kept on for a predetermined time (t1, 20㎳) after the start of shifting and is controlled to be on. The third shift control solenoid valve (SCSV-C) is continuously on.

The duty control is performed on the first and second pressure control solenoid valves PCSV-A and B, and the duty control is performed on the first pressure control solenoid valve as shown in FIG. 4.

That is, when the vehicle enters the 4-2 shift step S200 according to the driving condition, the TCU determines a control condition that satisfies the current state among the three control conditions (S210).

Among the control conditions, the first condition is t _o ≤ t _F , the second condition is t _F <t _o ≤ (t ₂ + t _F ), and the third condition is (t ₂ + t _F ) <t _o .

In the above, t _o is the pressure release time of the end clutch, the reference value is 96㎳, t ₂ is the movement time of the spool-B of the rear clutch release valve, the reference value is 60㎳, and t _F is the fill time and the reference value is 140 .

When the first condition is satisfied at step S210 (S220), the duty cycle is controlled by 0% from the shift start time to t ₂ + (t _F + t _o ) (S221), and t ₂ + (t _F + t _o After controlling the duty D _A1 from the time point), the duty control is performed at a slope of α1 (S222).

If the second condition is satisfied at step S210 (S230), the duty cycle is controlled by 0% from the start of shift to (t ₂ + t _F )-t _o (S231), (t ₂ + t _F )-t _o the duty from the time _A1 after the D control is carried out with a gradient duty control of the α1 (S232).

Further, if any of the third condition in the above step (S210) (S240), the shift after the start and at the same time by controlling the duty D _A1 is subjected to duty control the slope of the α1 (S241).

In the above, D _A1 is the duty value of the initial end clutch, the reference value is 72%, and α1 is the reference value is 32% / sec.

It is maintained and the D _A2 for a predetermined time after the duty control of the inclination α1 in the step (S222) (S232) (S241 ) is continued up to D _A2 (S250).

In the above, D _A2 is the end torque release duty.

If the synchronous detection is performed while maintaining D _A2 for a predetermined time in step S250, it is determined whether the power-off 4-2 control is performed in the power-on manual shift 4-2 state while maintaining the duty at 100% (S260). (S270).

Synchronization detection conditions in the _T2 is N - a N _T <N DELTA _T2.

If it is determined in step S270 that the current shift is the power-off 4-2 control in the power-on manual shift 4-2 state, the duty is maintained at 100% for the Thold time and then controlled at 0% (S271). If it is determined that the power-off 4-2 control is not performed in the on manual shift 4-2 state, the duty control of the first pressure control solenoid valve PCSV-A is terminated by controlling the duty to 0% (S272) (S280). .

In the above, the reference value of the Thold time is 60 ms.

And the second pressure control solenoid valve (PCSV-B) is made to the duty control as shown in Figure 5, that is, entering the 4-2 shift step (S300) according to the driving conditions, two control conditions in the TCU The control condition that satisfies the current state is determined (S310).

In the above control, the first condition is (t ₂ + t _F ) ≥ t ₀ , and the second condition is (t ₂ + t _F ) <t _o .

In the above, reference values of t _o , t ₂ , and t _F are the same as those of the first pressure control solenoid valve PCSV-A.

When the first condition is satisfied in the step S310 (S320), immediately after the shift starts, the duty 100% is maintained for t ₂ (S321), and after the duty 0% control is maintained for t _F (S322).

If the second condition is satisfied at step S310 (S330), the duty cycle is immediately controlled at 100% after the shift is started, and then maintained for [(t ₂ + {t _0- (t ₂ + t _F )}] (S331). ), And maintains for t _F after the duty 0% control (S332).

After maintaining the duty 0% for t _F in the step (S322) (S332), after the control by the duty D _B1 (N _T -N _F ) ≥ △ △ N _T1 is controlled by the β1 slope (S340).

In the step (S340), after (N _T -N _F ) ≥ ΔΔ _T1 controlled by the beta tilt, it is controlled by the β2 slope by adding ΔD _B (S350), in the state of continuing to maintain the step (S350) If synchronization is detected, the duty control of the second pressure control solenoid valve PCSV-B is terminated by controlling the duty to 0% (S370).

In the above, the duty D _B1 is 50% (0.5 × 2.56) when N ₀ ≥ 1500 RPM, 60% (0.6 × 2.56) when N ₀ <1500 RPM, and the duty D _B is 10% (0.1 × 10) when N ₀ ≥ 1500 RPM 2.56) and 5% (0.05 × 2.56) when N ₀ <1500 RPM.

And β1 and β2 are 28 and 16% / sec, and the synchronization detection condition is N _T2 -N _T <ΔN _T2 .

As described above, the first, second, and third shift control solenoid valves (SCSV-A, B, C) and the first and second pressure control solenoid valves (PCSV-A, B) are duty-controlled to perform 4-2 down skipping. In this case, according to the present invention, the duty control of the first pressure control solenoid valve (PCSV-A) at 100% before completion of synchronization, thereby releasing the operating pressure of the end clutch (C3) to abnormal vibration at the end of the 4-2 transmission. It is possible to prevent the occurrence in advance.

As described above, according to the present invention, by releasing the operating pressure of the end clutch before the synchronization is completed when the 4 → 2 down skipping, to minimize the occurrence of abnormal vibration generated at the end of the shift to improve the shifting performance and at the same time It is an invention that can improve the riding comfort.

Claims (9)

When the shift signal from the fourth speed to the second speed is input, the first shift control solenoid valve (SCSV-A) is turned off immediately after the shift start detection, and the second shift control solenoid valve (SCSV-B) is fixed after the shift start. The off state is maintained for a time t1 and then controlled to the on state, and the third shift control solenoid valve SCSV-C is continuously on, and the first and second pressure control solenoid valves PCSV-A are controlled. , B) duty-controlled 4-2 down skipping, When the first pressure control solenoid valve (PCSC-A) enters the 4-2 shift stage, the pressure release time t _o of the end clutch and the travel time and fill time of the spool-B of the rear clutch release valve are Determining a control condition that satisfies the present condition by comparing the condition, controlling the duty from 0% to D _A1 , and then controlling the duty with an α1 slope; Controlling the tilt of α1 to D _A2 in the above step and maintaining the state until the synchronization is detected, and increasing the duty to 100% when the synchronization is detected; In the above step, it is determined whether the current shift process is the power-off 4-2 control in the power-on manual shift 4-2 state. ; In the above step, if it is determined that the current shift process is not the power-off 4-2 control in the power-on manual shift 4-2 state, the 4-2 down skip of the automatic transmission for a vehicle is performed to control the duty to 0% to complete the shift. Shift control method of city. The method of claim 1, wherein the three control conditions, the first condition is t _o ≤ t _F , the second condition is t _F <t _o ≤ (t ₂ + t _F ), the third condition is (t ₂ + t _F 4) A shift control method at the time of 4-2 down skip of an automatic transmission for a vehicle, characterized in that <t _o . The method according to claim 2, when it meets the first condition above, the duty up from the transmission start t ₂ + (t _F + t _o) control 0%, and t ₂ + (t _F + t _o) of the duty from the time A shift control method at the time of 4-2 down skip of the automatic transmission for a vehicle, characterized in that the duty control is performed at the inclination of α1 after the D _A1 control. The method of claim 2, wherein if the second condition is satisfied, the duty is controlled by 0% from the start of the shift to (t ₂ + t _F )-t _o, and the duty is _adjusted from (t ₂ + t _F )-t _{o. A-} 1, the shift control method at the time of 4-2 down skip of the automatic transmission for a vehicle, characterized in that the duty control is performed by the slope of α1. The method according to claim 2, the shift control during the 4-2 skip-down of the vehicle automatic transmission, which if any of the third condition in the above, after the duty D at the same time as shifting start a control _A1 characterized in that the duty control made of an inclination of the α1 Way. The shift control method according to any one of claims 3, 4 and 5, wherein D _A1 has a reference value of 72% and α1 has a reference value of 32% / sec. The shift control method according to claim 1, wherein D _A2 has a reference value of 87%. The shift control method according to claim 1, wherein the Thold reference value is 60 ms. The shift control method according to claim 1, wherein the synchronous detection condition is N _T2 -N _T &lt; = N _T2 .