KR100239894B1 - A line pressure controller - Google Patents

Abstract

Appropriate line pressure setting is performed in the torque state period and the inertia state period during shifting.

In the torque state in which the engine output torque TQe and the inertia torque TQi are respectively calculated (S3, S4), and in the shifting speed, the engine output torque TQe is regarded as the gear train input torque TQ (S8). On the other hand, in the inertia state in an upshift, the addition value of engine output torque TQe and inertia torque TQi is set as gear heat input torque TQ (S9). Moreover, in the inertia state in downshift, the value which subtracted inertia torque TQi from engine output torque TQe is set as gear train input torque TQ (S11). Then, the gear train input torque TQ is converted into the line pressure PL to perform line pressure control (S12).

Description

Line pressure control device of automatic transmission

The present invention relates to a line pressure control device of an automatic transmission, and more particularly, to a technology for controlling the line pressure in response to an input torque to the gear train of the automatic transmission.

As a line pressure control apparatus according to the input torque of a gear train, there exist some conventionally, for example, as what was disclosed by Unexamined-Japanese-Patent No. 48-16058 and Unexamined-Japanese-Patent No. 4-72099.

The apparatus disclosed in Japanese Patent Laid-Open No. 48-16058 is a configuration for determining the line pressure as a function of engine output torque.

In addition, the apparatus disclosed in Japanese Unexamined Patent Publication No. 4-72099 is configured to determine a line value in proportion to the value obtained by multiplying the engine speed by a constant coefficient and the sum of the engine output torque.

By the way, it is preferable to make the line pressure at the time of speed change suitable for gear train input torque.

However, in the apparatus disclosed in Japanese Patent Laid-Open No. 48-16058, since the line pressure is determined on the basis of the engine output torque, even if a proper line pressure setting is made in a torque state not accompanied by a change in engine rotation during shifting, In the inertia state accompanied by the engine rotation change, there was a problem that the inertia torque component would be unsuitable for hydraulic pressure.

In the apparatus disclosed in Japanese Unexamined Patent Publication No. 4-72099, since the line pressure is determined by the sum of the inertia torque (the product of the engine speed and a constant coefficient) and the engine output torque, Even if an appropriate line pressure setting is performed in the inertia state, there is a problem that the hydraulic pressure of the inertia torque component is also unsuitable in the torque state.

The present invention has been made in view of the above problems, and an object thereof is to allow proper line pressure setting to be performed in a torque state and an inertia state during shifting, respectively.

1 is a block diagram showing the basic configuration of the present invention.

2 is a system configuration diagram of the embodiment.

3 is a flowchart showing the line pressure control in the embodiment.

4 is a timeline diagram showing the inertia torque during upshift.

5 is a timeline diagram showing the inertia torque during downshift.

* Explanation of symbols for main parts of the drawings

1: oil pump 2: solenoid valve

6-10: Hydraulic circuit 11: Control unit

12 engine 13 speed sensor

15: Throttle Valve 16: Throttle Sensor

17: air volume meter 19: vehicle speed sensor

In order to achieve this object, the line pressure control apparatus of the automatic transmission according to the present invention is the line pressure of the automatic transmission for controlling the line pressure supplied to the hydraulic circuit for controlling each transmission element of the automatic transmission constituting the power transmission system of the engine. As a control apparatus, it is comprised as shown in FIG.

In Fig. 1, the engine output torque detecting means detects the output torque of the engine, and the inertial torque detecting means detects the inertial torque during shifting. The inertial state detecting means detects an inertial state during shifting, and the torque state detecting means detects a torque state during shifting.

Here, the gear train input torque determining means determines the gear train input torque based on the engine output torque detected by the engine output torque detecting means in the torque state, and the engine heat torque detecting means detected in the inertial state. The gear train input torque is determined based on the engine output torque and the inertial torque detected by the inertial torque detecting means.

The line pressure calculating means calculates the line pressure based on the gear train input torque determined by the gear train input torque determining means, and the line pressure control means supplies the line pressure supplied to the hydraulic circuit based on the calculated line pressure. Adjust it.

Here, when the gear train input torque determining means is upshifted with acceleration, the gear train input torque in the inertia state is detected by the engine output torque detected by the engine output torque detecting means and the inertial torque detecting means. What is necessary is just to comprise so that it may be determined based on the added value of inertia torque.

Similarly, when the gear train input torque determining means is downshifted with acceleration, the gear train input torque in the inertia state is detected by the inertial torque detection means from the engine output torque detected by the engine output torque detection means. What is necessary is just to comprise so that it may determine based on the value which subtracted inertia torque.

According to this configuration, the torque state and the inertia state are detected during shifting, the gear train input torque is determined based on the engine output torque during the torque state, and the gear train input is determined by the engine output torque and the inertia torque in the inertia state. The torque is determined.

That is, in a torque state not accompanied by a change in engine rotation, the required line pressure is determined by a torque suitable for the engine output torque, and a demand matched by an engine output torque and an inertia torque in an inertial state involving a change in rotation. Line pressure is determined.

In this case, the engine rotation changes from high rotation to low rotation during upshift accompanied by acceleration, so that the kinetic energy of the engine is released as a torque, and in reverse, the engine rotation changes from low rotation to high rotation during downshift. The torque for the rotational rise is absorbed from the torque.

Therefore, the gear train input torque is determined on the basis of the addition of the engine output torque and the inertia torque released along with the lowering of rotation when the upshift is accompanied by the acceleration, and is absorbed by the rotational increase from the output torque of the engine when the downshift is performed. The gear train input torque was determined based on the subtracted inertia torque.

[Description of Preferred Embodiment]

An embodiment of the present invention will be described below.

In FIG. 2 showing an embodiment, the oil pump 1 is driven by an output shaft of the engine 12 with a torque converter of an automatic transmission not shown.

The pilot valve 3 regulates the discharge pressure of the oil pump 1 to the pilot pressure applied to the solenoid valve 2.

The solenoid valve 2 adjusts the pilot pressure to the throttle pressure in accordance with the operating conditions, and the pressure change valve 4 regulates the pilot pressure to the pressure change pressure in response to the throttle pressure, and actuates the pressure regulating valve 5.

In the pressure regulating valve (5), the oil pump discharge pressure is adjusted to a line pressure proportional to the pressure change pressure, and the torque converter (for power transmission) (6), for lubrication (7), for cooling (8) and for generating hydraulic pressure (9) and other 10 to each hydraulic circuit.

In addition, there is a valve on the pressure side of the actuating hydraulic pressure generating circuit 9 to engage the clutch, the hand brake, etc. in accordance with the gear position.

The control unit 11 incorporating the microcomputer for duty control of the solenoid valve 2 has an engine speed signal Ne from the speed sensor 13 for detecting the speed Ne of the engine 12 and an intake passage 14. Throttle opening degree signal TVO from the throttle sensor 16 which detects the opening degree TVO of the throttle valve 15 interlocked with the accelerator pedal provided in the above, and the intake air amount Qa of the engine 12 upstream of the throttle valve 15. To the intake air quantity signal Qa from the air flow meter 17, the water temperature signal Tw from the water temperature sensor 18 to detect the coolant temperature W in the cooling jacket of the engine 12, and the vehicle speed sensor 19. The vehicle speed signal VSP or the like detected by the input is input.

The control unit 11 performs the line pressure control of the automatic transmission as shown in the flowchart of FIG. 3 by a built-in microcomputer.

In addition, in the present embodiment, the functions as the gear train input torque determining means, the line pressure calculating means, and the line pressure control means are the control units in which the control unit 11 is provided in software as shown in the flowchart of FIG. (11), the functions as the torque state detecting means, the inertial state detecting means, the engine output torque detecting means, and the inertial state detecting means are realized by software functions of the various sensors and the control unit 11 described above.

The flowchart in FIG. 3 shows the line pressure control at the time of shifting. First, in the first step (S1 in the drawing. The following is the same), the intake air amount Qa of the engine 12, the engine speed Ne, The throttle valve opening degree TVO and the type of shift (upshift, downshift, etc.) are input.

In the next second step, the engine speed Ne at the time of detecting the inertia state (when detecting the rotational drop) is detected and this speed Ne is set as MAXNe.

In the third step, the engine output torque TQe is calculated as TQe = K × Qa / Ne based on the intake air amount Qa of the engine, the engine speed Ne, and a constant coefficient K.

In the fourth step, the inertia torque TQi accompanying the rotational change in the inertia state is calculated by the following method.

In other words, the target time of inertia is TIM, the gear ratio before shifting is G ₁ , the gear ratio after shifting is G ₂ , and the inertia of the turbine part of the torque converter is Ki. Assuming that the ratio changes, the rotation at the end of the inertia state is obtained as G ₂ / G ₁ × MAXNe, so that the inertia torque TQi accompanying the rotation change in the inertia state is

TQi = Ki × MAXNe / TIM × (G ₁ / G ₂ ) G ₁

It is calculated as

In the next fifth step, it is determined whether or not the shift is in progress, and if it is shifting, it is again determined in the sixth step whether or not the upshift accompanying acceleration is determined.

In the case of upshift shifting, it progresses to 7th step and determines whether it is a torque state in the upshift shift. In the upshift, a period of time that does not involve a change in rotation from the start of the shift until the rotational drop (inertial state) is detected is detected as the torque state, and when it is in the torque state, the process proceeds to the eighth step and the operation calculated in the third step is performed. The engine output torque TQe is called the gear train input torque TQ.

The engine output torque TQ can be regarded as the gear train input torque TQ as it is during the torque state not accompanied by a change in engine rotation, and the line pressure PL is preferably set to a value suitable for the gear train input torque TQ. By setting the input torque TQ in the eighth step, the appropriate line pressure PL can be set.

On the other hand, during the upshift shifting, when the inertia state (period from the rotational drop detection to the end of the shift) accompanied by the engine rotation fluctuation is performed, the process proceeds to the ninth step, and the engine output torque TQe calculated in the third step is calculated in the fourth step. The value obtained by adding one inertia torque TQi is determined as the gear train input torque TQ.

That is, in the upshift shifting, since the engine rotation decreases, the kinetic energy of the engine is released as a torque (see FIG. 4). Therefore, the torque obtained by adding the inertia torque TQi generated along with the rotation decrease to the engine output torque TQe. Is the gear train input torque TQ.

On the other hand, if it is found that the sixth step is not an upshift but a downshift accompanied by acceleration, then the flow advances to the tenth step and is the torque state (see FIG. 5) not accompanied by a change in engine rotation in this downshift? Determine whether or not.

And in the torque state which does not involve a change of engine rotation, it progresses to 8th step and sets the engine output torque TQe computed in the 3rd step as gear train input torque TQ.

If it is determined that the motor is in an inertia state with a change in engine rotation in the downshift, the process proceeds to step 11, and the value obtained by subtracting the inertia torque TQi calculated in the fourth step from the engine output torque TQe calculated in the third step. Is the gear train input torque TQ.

That is, since the engine rotation increases in downshift shifting, the kinetic energy required for such an increase must be absorbed from the engine output torque (see FIG. 5), so that the inertia torque TQi absorbed by the rotation increase in engine output torque TQe. The torque after subtracting is set as the gear train input torque TQ.

In the inertia state as described above, the engine output torque TQ is corrected for the inertia torque TQi generated along with the rotational change, and furthermore, the release or absorption of the inertia torque TQi occurs due to the rotational change direction (shift direction). Therefore, since the correction direction by the inertia torque TQi is changed depending on the shift direction, the gear train input torque TQ can be precisely resolved even in the inertia state in which the inertia torque TQi occurs, so that the line pressure PL can be properly adjusted. Can be controlled.

When the gear train input torque TQ is determined as described above, in step 12, the gear train input torque TQ is switched to the line pressure PL using a switching table, and the line pressure is adjusted based on the line pressure PL obtained by the switching. Do this.

As described above, according to the present invention, the period during the shift is divided into a torque state not accompanied by a change in engine rotation and an inertial state accompanied by a change in engine rotation, and in the torque state based on the engine output torque. In the state, since the gear train input torque is determined based on the engine output torque and the inertia torque, the gear train input torque can be accurately determined irrespective of the shift period, so that the line pressure can be controlled at an appropriate value. There is.

The inertia torque acts as the emission energy during the upshift and as the absorbed energy during the downshift so that the correction direction of the inertia torque is changed in response to the shift direction. There is an effect that can control the line pressure to an appropriate value.

Claims (3)

A line pressure control device of an automatic transmission for controlling a line pressure supplied to a hydraulic circuit for controlling each shift element of an automatic transmission constituting a power transmission system of an engine, comprising: engine output torque detecting means for detecting an output torque of the engine; Inertial torque detecting means for detecting inertial torque during shifting, inertial state detecting means for detecting inertial state during shifting, torque state detecting means for detecting torque state during shifting, and the engine output during the torque state. The gear train input torque is determined based on the engine output torque detected by the torque detecting means, and in the inertial state based on the engine output torque detected by the engine output torque detecting means and the inertial torque detected by the inertial torque detecting means. The gear train input torque determining means for determining the gear train input torque, and the gear train input torque determining means. And a line pressure calculating means for calculating a line pressure based on the gear train input torque, and a line pressure control means for adjusting the line pressure supplied to the hydraulic circuit based on the line pressure calculated by the line pressure calculating means. Line pressure control device of an automatic transmission, characterized in that configured. The engine output torque and the inertia torque detection according to claim 1, wherein the gear train input torque determining means detects the engine heat torque and the inertia torque detected by the engine output torque detecting means when the gear train input torque determining means performs an upshift accompanied by acceleration. A line pressure control device for an automatic transmission, characterized in that the determination is made based on the added value of the inertia torque detected by the means. The engine heat torque according to claim 1 or 2, wherein the gear train input torque during the inertia state is determined by the engine output torque detection means when the gear train input torque determining means is down-shifted with acceleration. And an inertial torque detected by said inertial torque detecting means on the basis of a value subtracted.