JPH03219161A - Line pressure learning control device for automatic transmission - Google Patents

Abstract

PURPOSE:To improve speed change shock performance in a large degree by learning the dispersion and degraded parts of an engine and an automatic transmission minutely so as to make waveform at the time of speed change the target waveform. CONSTITUTION:The output shaft torque of an automatic transmission is sampled by a torque waveform detecting means (f). Speed change time, which is the torque fluctuation time, is computed by a speed change time computing means (g) from the detected torque waveform during speed change. The torque pop quantity, which is the integrated value of torque fluctuation, is computed by a torque pop quantity computing means (h). The speed change time is then compared to its target value by a first correction quantity updating means (i) so as to set the first correction quantity increasingly or decreasingly in the direction of coinciding with the target value. The first correction quantity data of a storage means (b) is reloaded, and the torque pop quantity is compared with its target value by a second correction quantity updating means (j) so as to set the second correction quantity increasingly or decreasingly in the direction of coinciding with the target value and rewrite the second correction quantity data of the storage means (b).

Description

[Detailed description of the invention] <Industrial application field> The present invention is an automatic transmission for automobiles (automatic transmission).

The present invention relates to a line pressure learning control device that learns and controls line pressure during gear changes in a drive transmission.

<Conventional technology> In automatic transmissions for automobiles, the discharge pressure of an oil pump is regulated to obtain line pressure, which is then supplied to a hydraulic circuit to control the operating hydraulic pressure of a torque converter and various speed change elements in a gear type transmission. This line pressure is controlled to an appropriate oil pressure according to the engine output.

In other words, in an automatic transmission, the line pressure that is the source of the operating oil pressure for the torque converter and various transmission elements needs to be adjusted to the appropriate oil pressure according to the engine output, and if the oil pressure is higher than the appropriate oil pressure during gear shifting, the torque transmission As efficiency increases, engine vibrations and shift shocks are transmitted to the output shaft, increasing noise and vibration. Also, if the oil pressure is lower than the appropriate oil pressure during gear shifting, slipping will occur, reducing transmission efficiency, and
This causes a feeling of lag in gear shifting, deteriorates the durability of the automatic transmission, and further deteriorates fuel efficiency.

Therefore, in the past, the line pressure was controlled by having a map that predetermined the optimal line pressure according to the throttle valve opening, etc., and driving the line pressure actuator based on this map. (Refer to Publication No.-9054).

Furthermore, during gear shifting, learning control is performed to keep the gear shifting time constant.

That is, when shifting, the basic line pressure is set based on the throttle valve opening etc. with reference to the basic line pressure map on the ROM, and the basic line pressure is set based on the throttle valve opening etc. with reference to the correction amount map on the RAM. Set the correction amount, add the correction amount to the basic line pressure, set the line pressure, and control based on this, while detecting the shift time from the time when the engine speed decreases during the shift, When the shift time is longer than the target value, the correction amount is set to the increasing side in order to increase the line pressure and the correction amount map on the RAM is rewritten, and when the shift time is shorter than the target value, the line pressure is decreased. Therefore, the correction amount is set to the decreasing side and the correction amount map on the RAM is rewritten.

<Problems to be Solved by the Invention> However, conventional line pressure learning control during gear shifting only changes the line pressure so that the target shifting time is achieved, and does not correct the characteristics of the line pressure actuator. Ta.

In other words, it is intended to make only the time of torque fluctuation during gear shifting constant, not the amount of torque fluctuation, but to correct output shaft torque or deterioration due to variations in the engine or automatic transmission. However, there was a problem in that the performance of the shift shock was inconsistent.

In view of these conventional problems, the present invention aims to significantly improve shift shock performance by learning and controlling not only the time of torque fluctuation during gear shifting but also the amount of torque fluctuation to a target value. With the goal.

<Means for Solving the Problems> Therefore, the present invention provides a line pressure learning control device for an automatic transmission that learns and controls line pressure during gear shifting, as shown in FIG. Provides an apparatus comprising the means of j).

(a) Basic line pressure setting means for setting the basic line pressure based on the engine load (b) Rewritable storage means (C) that stores the first correction amount and the second correction amount for each area of the engine operating state. (d) A line for calculating the line pressure from the basic line pressure, the first correction amount, and the second correction amount. Pressure calculation means (e) Line pressure control means for controlling line pressure by driving a line pressure actuator based on the calculated line pressure) Sampling the signal from the torque sensor that detects the output shaft torque of the automatic transmission. Torque waveform detection means (phase) that detects the torque waveform during shifting (phase) Shifting time calculation means (c) that calculates the shifting time, which is the time of torque fluctuation, from the torque waveform during shifting Torque jump amount calculation means (i) for calculating the torque jump amount, which is a value, compares the shifting time with the target value, increases or decreases the first correction amount in a direction that matches the target value, and sets the first correction amount in the direction of matching the target value, A first correction amount updating means (j) for rewriting data of the first correction amount; compares the torque jump amount with its target value, increases or decreases the second correction amount in a direction that matches the target value; Function of the second correction amount updating means for rewriting the second correction amount data of Setting the line pressure, and also from the storage means (b),
The search means (C) searches for the first correction amount and the second correction amount based on the engine operating state.

Then, the line pressure calculation means (d) calculates the line pressure from the basic line pressure, the first correction amount, and the second correction amount,
The line pressure control means (e) drives a line pressure actuator to control the line pressure.

On the other hand, the torque waveform detection means samples the output shaft torque of the automatic transmission and detects the torque waveform during gear shifting. Then, from the torque waveform during the shift, the shift time calculation means ((2) calculates the shift time (T in Figure 6), which is the time of torque fluctuation, and the torque jump amount calculation means (
5), the torque jump amount (S in FIG. 6), which is the integral value of the torque fluctuation amount, is calculated. Then, the first correction amount updating means (i) compares the shifting time with the target value, increases or decreases the first correction amount in a direction that matches the target value, and performs the first correction in the storage means (b). The second correction amount updating means (j) compares the torque jump amount with its target value, sets the second correction amount to increase or decrease in a direction that matches the target value, and the storage means (j) rewrites the second correction amount data. Rewrite the data of the second correction amount in b).

In this way, by controlling the shift time and torque jump amount to the target values, the torque waveform during gear shifting, which is approximately defined by the torque fluctuation time and the integral value of the torque fluctuation amount, is controlled to the target waveform. to improve shift shock performance.

<Example> An embodiment of the present invention will be described below.

Referring to FIG. 2, an automatic transmission 2 is provided on the output side of the engine 1. The automatic transmission 2 includes a torque converter 3 interposed on the output side of the engine 1, a gear type transmission 4 connected via this torque converter 3, and this gear type transmission 4.
It is equipped with a hydraulic actuator 5 that connects and releases various speed change elements therein. Although the hydraulic pressure applied to the hydraulic actuator 5 is ON/OFF controlled via various electromagnetic valves, only shift electromagnetic valves 6A and 6B for automatic gear shifting are shown here. Note that 7 is an output shaft of the automatic transmission 2.

Here, the torque converter 3 and the hydraulic actuator 5
An oil pump 8 driven by the input shaft of the gear type transmission is used to obtain line pressure, which is the working oil pressure for the orifice 9 and the electromagnetic valve 10. A pressure modifier valve 11 and a pressure regulator valve 12 are provided.

The electromagnetic valve 10 is duty-controlled as described below, and obtains a pilot pressure based on the discharge pressure of the oil pump 8 guided through the orifice 9. The pressure modifier valve 11 amplifies the pilot pressure. The pressure regulator valve 12 regulates the discharge pressure from the oil pump 8 to a line pressure proportional to the pilot pressure from the pressure modifier valve 11, and sends it to a hydraulic circuit such as the torque converter 3 and the hydraulic actuator 5.

Signals are input to the control unit 13 from various sensors.

As the various sensors described above, a potentiometer-type throttle sensor 15 is provided that detects the opening degree TVO of the throttle valve 14 in the intake system of the engine 1.

Further, a crank angle sensor 16 is provided on the crankshaft of the engine 1 or a shaft that rotates in synchronization with the crankshaft. The signal from the crank angle sensor 16 is, for example, a pulse signal for each reference crank angle, and the engine speed N is calculated from the period.

Further, a hot wire type air flow meter 17 for detecting the intake air flow rate Q is provided in the intake system of the engine 1. From this intake air flow rate Q and engine speed N, the basic fuel injection amount Tp = KXQ/N (K is a constant) is calculated, which is the basis for calculating the fuel injection amount by the electronically controlled fuel injection device (fuel injector). .

Further, a vehicle speed sensor 18 is provided which obtains a rotation signal from the output shaft 7 of the automatic transmission 2 and detects the vehicle speed VSP.

Further, a magnetostrictive torque sensor 19 is provided which is attached to the output shaft 7 of the automatic transmission 2 and detects the output shaft torque Tr.

As shown in FIG. 3, the control unit 13 is an integrated type that incorporates a CPU 13a for engine control (fuel injection and ignition timing control) and a CPU 13b for automatic transmission control, and is accessible from both CPUs 13a and 13b. It uses 13C of dual-port RAM. With this configuration, data such as the engine speed N and the basic fuel injection amount Tp calculated by the engine control CPU 13a can be used by the automatic transmission control CPU 13b.

Automatic transmission control CPU 1 of control unit 13
3b mainly performs speed change control and line pressure control.

Shift control is performed in accordance with the operation position of the select lever. In particular, when the select lever is in the D range, the shift position from 1st to 4th gear is automatically set according to the throttle valve opening TVO and vehicle speed VSP, and the shift control is performed in accordance with the operating position of the select lever. 0N of solenoid valves 6A and 6B
-OFF combination is controlled, and the hydraulic actuator 5
The gear type transmission 4 is controlled to that shift position via.

The line pressure control is performed using the electromagnetic valve 1 as a line pressure actuator according to the line pressure control routine shown in FIG.
0 under duty control. Here, the line pressure can be increased by increasing the duty (valve open time ratio).

Next, the line pressure control routine shown in FIG. 4 will be explained.

In step 1 (denoted as Sl in the figure; the same applies hereinafter), it is determined whether or not a gear shift is being performed.

If the gear is not being shifted, proceed to step 2, refer to a normal map that predetermines the optimal line pressure LP according to the throttle valve opening TVO, and set the line pressure LP by searching from the actual throttle valve opening TVO. .

Then, the process proceeds to step 8, where a duty corresponding to this line pressure P is outputted to drive the electromagnetic valve 10, thereby obtaining the optimum line pressure.

If the gear is being changed, steps 3 to 7 are executed to control the line pressure during the gear change, and the process proceeds to step 8.

In order to control the line pressure during such gear shifting, a map (hereinafter referred to as LPO map) that defines the basic line pressure LPO according to the throttle valve opening TVO (or basic fuel injection amount Tp) representing the engine load is stored in the ROM. In addition to being provided, R
On the AM, there is a map (hereinafter referred to as Cl map) in which the first correction amount C1 is determined for each area of the engine operating state determined by the engine speed N and the basic fuel injection fTp, and a map (hereinafter referred to as Cl map) that defines the first correction amount C1 for each area of the same engine operating state. A map (hereinafter referred to as a C2 map) defining the 2 correction amount C2 is provided.

Here, the Cl map and C2 map correspond to storage means.

Note that the LPO map, Cl map, and C2 map are provided for each type of shift (1st speed → 2nd speed, 2nd speed → 3rd speed, etc.).

In step 3, one of each of a plurality of LPO maps, Cl maps, and C2 maps is selected depending on the type of shift (1st speed → 2nd speed, 2nd speed → 3rd speed, etc.).

In step 4, the basic line pressure LP is searched and set based on the throttle valve opening TVO with reference to the LPO map. This part corresponds to the basic line pressure setting means.

In step 5, the first correction amount C1 (initial value is 0) is searched based on the engine speed N and the basic fuel injection amount Tp with reference to the C1 map.

In step 6, the second correction amount C2 (initial value is O) is searched based on the engine speed N and the basic fuel injection amount Tp with reference to the C2 map. These steps 5 and 6 correspond to the search means.

In step 7, the basic line pressure LPO, the first correction amount C1
and the second correction amount C2 to calculate the line pressure LP as shown in the following equation. This part corresponds to the line pressure calculation means.

LP=LPO+C1+C2 In step 8, by outputting the duty corresponding to this line pressure LP and driving the electromagnetic valve IO,
Obtain optimal line pressure. This part corresponds to the line pressure control means.

The first correction amount CI and the second correction amount C2 are learned by a learning routine shown in FIG.

Next, the learning routine shown in FIG. 5 will be explained.

In step 11, it is determined whether or not the gear is being changed.

If the speed is being changed, the process proceeds to step 12, where it is determined whether the sampling timing is every 2 ms.

Then, only in the case of sampling timing, the process proceeds to step 13 to sample the signal from the torque sensor 19 (output shaft torque Tr), and in the next step 14 sets a flag F to indicate that sampling is in progress.

Thereby, the torque waveform during gear shifting can be detected as shown in FIG. Therefore, steps 11 to 14 correspond to the torque waveform detection means.

If the gear is not being shifted, proceed to step 15 and set the flag F.
Determine whether or not is 1.

If F=1, it means that the speed change is completed (sampling is completed), so steps 16 to 27 are executed to perform learning.

In step 16, a waveform analysis of the torque waveform during shifting is performed, and the shifting time 1゛ (Sec.
; see FIG. 6), and also calculate the torque jump amount S (kgm*s; see FIG. 6), which is the integral value of the torque fluctuation amount. Therefore, this portion corresponds to the shift time calculation means and the torque jump amount calculation means.

In step 17, the engine speed N and the basic fuel injection amount Tp
Based on the actual N and Tp, refer to a map in the ROM that defines the target shift time (hereinafter referred to as target T) and target torque jump amount (hereinafter referred to as target S) for each area of the engine operating state determined by Then, the target T and target S are searched.

In step 18, the type of gear change (1st gear → 2nd gear, 2nd gear → 3rd gear)
speed, etc.), each from multiple 01 manbu, C2 map.
Select one.

In step 19, with reference to the C1 map, the engine speed N
The first correction amount CI (initial value is 0) to be updated is searched based on the basic fuel injection amount Tp and the basic fuel injection amount Tp.

In step 20, the correction amount Δ for the first correction amount is determined based on the deviation of the shift time T from the target T according to the following equation.
Calculate C1. Note that K1 is a constant (for example, 0.5).

ΔC1=(T-Target T)XK In step 21, the current first correction amount CI
A new first correction amount C1 is calculated by adding the correction amount ΔC1 to .

C1=C1±8Cl In step 22, the first
Rewrite the correction amount CI data.

Here, steps 19 to 22 correspond to the first correction amount updating means.

In step 23, with reference to the C2 manbu, the engine speed N
The second correction amount C2 (initial value is O) to be updated is searched based on the basic fuel injection amount Tp.

In step 24, a correction amount ΔC2 for the second correction amount is calculated based on the deviation of the torque jump amount S from the target S according to the following equation. Note that K2 is a constant (for example, 0.5
).

ΔC2=-(S-Target 5)xK2 In step 25, the current second correction amount C2 is calculated according to the following formula.
A new second correction amount C2 is calculated by adding the correction amount ΔC2 to .

C2=C2+ΔC2 In step 26, the second
Rewrite the data of the correction amount C2.

Here, the sections 123 to 26 correspond to the second correction amount updating means.

After this, in step 27, flag F is reset.

<Effects of the Invention> As explained above, according to the present invention, the shift shock performance can be significantly improved by carefully learning the dispersion and deterioration of the engine and automatic transmission so that the torque waveform during gear shifting becomes the target waveform. The effect of this is that it is possible to achieve significant improvements.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram showing the configuration of the present invention, Fig. 2 is a system diagram showing an embodiment of the invention, Fig. 3 is a block diagram of the control unit, Fig. 4 is a flowchart of the line pressure control routine, FIG. 5 is a flowchart of the learning routine, and FIG. 6 is a diagram showing the torque waveform during gear shifting. 1... Engine 2... Automatic transmission 7... Output shaft 8... Oil pump 10... Solenoid valve
11... Pre-social modifier valve 12...
・Pressure regulator HARTZ 13...Control unit 15...Throttle sensor -9...
torque sensor

Claims (1)

[Scope of Claims] A line pressure learning control device for an automatic transmission that learns and controls line pressure during gear shifting, comprising: a basic line pressure setting means that sets a basic line pressure based on the engine load; a rewritable storage means that stores the first correction amount and the second correction amount in the storage means; a search means that searches the storage means for the first correction amount and the second correction amount based on the engine operating state; and a basic line pressure. Line pressure calculation means for calculating line pressure from the first correction amount and the second correction amount; Line pressure control means for controlling the line pressure by driving a line pressure actuator based on the calculated line pressure; automatic shifting; Torque waveform detection means detects the torque waveform during gear shifting by sampling a signal from a torque sensor that detects the output shaft torque of the machine; and a gear shifting time that calculates the gear shifting time, which is the time of torque fluctuation, from the torque waveform during gear shifting. a calculation means, a torque jump amount calculation means for calculating a torque jump amount which is an integral value of the torque fluctuation amount from a torque waveform during gear shifting; and a torque jump amount calculation means that calculates a torque jump amount which is an integral value of the torque fluctuation amount from a torque waveform during shifting; a first correction amount updating means for increasing or decreasing a first correction amount and rewriting data of the first correction amount in the storage means; A line pressure learning control device for an automatic transmission, comprising: second correction amount updating means for increasing or decreasing a second correction amount and rewriting data of the second correction amount in the storage means.