KR100244535B1 - Shift control device - Google Patents

Abstract

Upshift prohibition control, such as when driving uphill, is performed more appropriately to prevent shift hunting and to improve fuel cost and operability.

Upon generation of an upshift (e.g., three speeds to four speeds) request, the first driving force calculating means e calculates the driving force at the current shift stage (three speeds) on the basis of the current engine load. The running resistance calculating means f calculates the running resistance based on the calculation result. The second driving force calculating means g sets the maximum driving force at the next shift stage (4 speed) on the downshift line from the corresponding next shift stage (4 speed) to the current shift stage (3 speed) in the shift pattern diagram. Calculated based on the engine load corresponding to the current vehicle speed. The comparison means h compares the running resistance with the maximum driving force. The upshift prohibition means i prohibits the upshift to the next shift stage (4 speeds) when the maximum driving force is smaller than the travel resistance.

Description

Transmission control device of automatic transmission

The present invention relates to a shift control apparatus for a motor vehicle automatic transmission.

Conventionally, as a control for preventing shift hunting during uphill driving in a control for determining a shift stage in a shift pattern diagram in response to a vehicle speed and an engine load (for example, a throttle opening), (1) Japanese Patent Application Laid-Open No. 1-55346. And (2) Japanese Patent Laid-Open No. 63-167158, and (3) Japanese Patent Laid-Open No. 4-145257.

These controls are controls characterized by comparing the running resistance at the time of generation of the upshift request with the driving force after the expected upshift, and prohibiting the upshift when the running resistance exceeds the driving force.

By the way, in the shift pattern diagram shown in FIG. 13, for example, when the vehicle speed changes from A to B at 3 speeds, an up shift request from the C point on the upshift line (vehicle speed VSP ₁ ) to 4 speeds is generated. Occurs. However, when the running resistance at point C exceeds the driving force (output torque) of four speeds, it is preferable to prohibit the upshift to four speeds. In this case, it is preferable that the driving force (output torque) of the four speeds compared in this case be the maximum driving force (output torque) that can be generated at the four speeds.

On the other hand, Japanese Patent Application Laid-Open No. 1-55346 of (1) calculates the gear ratio i of the new shift stage and the engine speed or vehicle speed accompanying i and calculates the corresponding engine torque. Is detected and the output torque (driving force) is calculated by multiplying by i.

In Japanese Patent Application Laid-Open No. 63-167158, (2), engine output (driving force) is based on calculation means for calculating engine output at all shift stages between the commanded shift stage and the current shift stage. ) Is calculated.

Therefore, in these two prior arts, the driving force after the upshift is the driving force at point C, so even when the driving force such as traveling resistance is obtained by stepping hard on the accelerator even at four speeds, the upshift is prohibited. As a result, there is a problem that the fuel economy is deteriorated and noise is generated due to high engine speed.

In addition, in Japanese Patent Laid-Open No. 4-145257, (3), since the driving force is the driving force when the throttle is completely opened at each speed change stage, the throttle opening degree at which the driving resistance and the driving force are equal is four. Speed → 3 speed downshift Although it is upshifted to 4 speeds when it is between the opening degree (D point) and full opening (E point) on the line, it is downshifted to 3 speeds to produce driving force such as driving resistance. There is a problem that the shift hunting of 3 speed → 4 speed → 3 speed occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional problem, and an object thereof is to more appropriately perform an upshift prohibition control at the time of driving uphill and to achieve both prevention of shift hunting and improvement of fuel cost and operability.

1 is a functional block diagram showing the configuration of the first invention.

2 is a functional block diagram showing the configuration of the second invention.

3 is a functional block diagram showing the configuration of the third invention.

4 is a system diagram showing an embodiment.

5 is a flowchart of the first half of the shift control routine.

6 is a flowchart of the second half of the shift control routine (first invention).

7 is a flowchart of the second half of the shift control routine (second invention).

8 is a flowchart of the second half of the shift control routine (third invention).

9 is a diagram showing a shift pattern diagram.

10 shows a map for calculating the turbine torque.

11 shows a map for calculating rotational resistance + air resistance.

12 shows a method of calculating the downshift throttle opening degree.

13 is a view showing a conventional problem.

<Explanation of symbols for main parts of drawing>

1: engine 2: automatic transmission

6A, 6B: Shift solenoid valve 7: Control unit

9: vehicle speed sensor 11: throttle sensor

12: crank angle sensor

To achieve this object, the present invention provides a vehicle speed detecting means a for detecting a vehicle speed as shown in FIG. 1, an engine load detecting means b for detecting an engine load, a detected vehicle speed and an engine load. A transmission stage selection means c for selecting a shift stage of the transmission based on the shift pattern diagram and a shift command means d for generating an upshift request or a downshift request based on the selection result. On the premise of the shift control apparatus of FIG.

[First invention]

It is configured as shown in FIG.

The first driving force calculating means e calculates the driving force at the current speed change stage based on the current engine load.

The running resistance calculating means f calculates the running resistance based on at least the calculation result of the first driving force calculating means e.

The second driving force calculating means g calculates the driving force at the other shift stage based on the engine load corresponding to the current vehicle speed on the downshift line of the other shift stage in the shift pattern diagram.

The comparison means h compares the calculation result of the traveling resistance calculation means f with the calculation result of the second driving force calculation means g.

The upshift prohibition means i prohibits the upshift to another shift stage when the calculation result of the second driving force calculation means g is smaller than the calculation result of the travel resistance calculation means f, in accordance with the comparison result of the comparison means h. do.

[2nd invention]

It is comprised as shown in FIG.

The difference from the first is that the third driving force calculating means j is used in place of the second driving force calculating means g.

The third driving force calculating means j, calculates the driving force at another speed change stage based on a value obtained by adding a predetermined value to the current engine load.

As a result, the comparison means h, compares the calculation result of the travel resistance calculation means f with the calculation result of the third driving force calculation means j. Further, the upshift prohibiting means i performs an upshift to another shift stage when the calculation result of the third driving force calculating means j is smaller than the calculation result of the traveling resistance calculating means f according to the comparison result of the comparing means h. Prohibit.

[Third invention]

It is comprised as shown in FIG.

In addition to the said 2nd drive force detection means g, the 4th drive force calculation means m and the 5th drive force calculation means n are used for the 1st degree and another part.

The fourth driving force calculating means m calculates the driving force at the other speed change stage based on the current engine load.

The fifth driving force calculating means n calculates the driving force at another shift stage based on the calculating result of the second driving force calculating means j and the calculating result of the fourth driving force calculating means m.

As a result, the comparison means h compares the calculation result of the travel resistance calculation means f with the calculation result of the fifth driving force calculation means n. Further, the upshift prohibiting means i performs an upshift to another shift stage when the calculation result of the fifth driving force calculating means n is smaller than the calculation result of the traveling resistance calculating means f in accordance with the comparison result of the comparing means h. Prohibit.

[Etc]

The upshift prohibition means i may hold the current shift stage or may move the upshift line from the current shift stage to another shift stage in the shift pattern diagram.

Next, the operation will be described. Here, for example, it is assumed that an upshift request of 3 speeds to 4 speeds has occurred, and it is assumed that another shift stage is the next shift stage.

In the first aspect of the present invention, when an upshift (3 speeds → 4 speeds) request is generated, the driving force (maximum driving force after shifting) at the next shift stage (4 speeds) is determined by the second driving force calculating means g. Calculation is based on the engine load corresponding to the current vehicle speed on the downshift line from the next shifting stage (4 speeds) to the current shifting stage (3 speeds).

By comparing this with the travel resistance, the upshift is prohibited when the travel resistance is less than the travel resistance.

In the second aspect of the present invention, when an upshift (3 speeds → 4 speeds) request is generated, the driving force (additional drive force after shifting) at the next shift stage (4 speeds) is determined by the third drive force calculating means j. It calculates based on the value which added predetermined value to the engine load.

By comparing this with the travel resistance, the upshift is prohibited when the travel resistance is less than that.

In the third aspect of the present invention, when an upshift (3 speeds to 4 speeds) request is generated, the driving force (maximum driving force after shifting) at the next shift stage (4 speeds) is determined by the second driving force calculating means g. A fourth driving force calculation means, based on the engine load corresponding to the current vehicle speed on the downshift line from the next shift stage (4 speeds) to the current shift stage (3 speeds) With m, the driving force (actual driving force after shifting) at the next speed change stage (4 speeds) is calculated based on the current engine load.

Then, the fifth driving force calculating means n, based on the calculation result of the second driving force calculating means j and the calculation result of the fourth driving force calculating means m, drive force at the next shift stage (4 speeds) Additional driving force).

Then, when the driving force of the calculation result of the fifth driving force calculating means n is compared with the running resistance, the upshift is prohibited when the running resistance is lower.

[Description of Preferred Embodiment]

An embodiment of the present invention will be described below.

In FIG. 4, the automatic transmission 2 is provided in the output side of the engine 1. As shown in FIG. The automatic transmission (2) is coupled to and released from a torque converter (3) interposed on the output side of the engine (1), a gear transmission (4) connected via the torque converter, and various transmission elements in the gear transmission (4). It is equipped with the hydraulic actuator 5 which performs an operation. The operating hydraulic pressure for the hydraulic actuator 5 is controlled on and off by interposing various solenoid valves, in which only the shift valves 6A and 6B for automatic shifting are displayed.

The control unit 7 receives signals from various sensors. As the above various sensors, a vehicle speed sensor 9 is provided which obtains a rotation signal from the output shaft 8 of the automatic transmission 2 and detects the vehicle speed (output shaft rotational speed) VSP.

In addition, a potentiometer-type throttle sensor 11 for detecting the opening degree TVO of the throttle valve 10 of the intake system of the engine 1 is provided.

Moreover, the crank angle sensor 12 is provided in the crank shaft of the engine 1 or the shaft which rotates in synchronization with this. The signal from the crank angle sensor 12 is, for example, a pulse signal for each reference crank angle, and the engine speed Ne is calculated from the period.

The control unit 8 is equipped with a microcomputer and performs shift control on the basis of signals from the various sensors.

The shift control automatically sets a shift stage of one speed to four speeds in accordance with a shift control routine to be described later, controls a combination of on and off of the solenoid valves 6A and 6B for shifting the hydraulic actuator 5. The gear transmission 4 is controlled through the shift stage via the transmission.

Next, the shift control routine of FIGS. 5 to 6 which is an embodiment corresponding to the first invention will be described. In addition, this routine is executed every predetermined time.

In step 1 (described in the drawing as S1, which is the same below), the vehicle speed VSP is detected based on the signal from the vehicle speed sensor 9. This portion corresponds to the vehicle speed detecting means.

In step 2, the throttle valve opening degree TVO is detected as the engine load based on the signal from the throttle sensor 11. This part corresponds to the engine load detection means.

In step 3, the shift stage is selected by referring to the shift pattern diagram in which the shift stage is determined in response to the vehicle speed VSP and the throttle valve opening degree TVO as shown in FIG. This part corresponds to the gear shift selection means. In addition, in the shift pattern diagram of FIG. 9, the solid line shows an up shift line, and the dotted line shows the down shift line.

In step 4, an upshift request or downshift request is generated as needed based on the selected shift stage, and the next shift stage is determined. This part corresponds to a shift command means. In the case where the current is 3 speeds and the selected gear stage is 4 speeds, of course 4 speeds are the next gear stages, but when the current is 2 speeds and the selected gear stages are 4 speeds, 3 speeds are the next gear stages.

If there is neither an upshift request nor a downshift request, the routine is terminated as it is. If there is a downshift request, the routine advances to step 5, after performing the downshift to the next shift stage, the routine is terminated.

When there is a demand for an upshift (e.g., 3 speeds to 4 speeds), the process advances to step 6 and later to determine whether the up shift is appropriate.

In step 6, the turbine torque Tt _CGP is calculated based on the current throttle valve opening degree TVO and the turbine rotation speed Nt with reference to the drawing shown in FIG. The turbine speed Nt is calculated by the engine speed Ne and the torque converter characteristics.

In step 7, based on the calculated turbine torque Tt _CGP , the driving force (current driving force) F1 at the current shift stage (for example, three speeds) is calculated according to the following equation.

F1 = Tt _CGP X CG _RATIO XK

In addition, CG _RATIO is a gear ratio of the current shift stage (3 speeds), K is an integer determined according to the tire radius and the like.

In step 8, the acceleration resistance RESI _a is calculated according to the following equation.

REST _a = △ VSP XWXK

ΔVSP is the vehicle speed change amount, W is the vehicle weight, and K is an integer.

In step 9, the rolling resistance + air resistance RESI _rl are calculated at the vehicle speed VSP with reference to the analysis diagram shown in FIG.

In step 10, the driving resistance RESI _ALL is calculated by subtracting the acceleration resistance RESI _a and the rotational resistance + air resistance RESI _rl from the current driving force F1 as follows.

RESI _ALL = F1-RESI _a -RESI _rl

Here, the parts of steps 6 and 7 correspond to the first driving force calculating means and the parts of steps 8 to 10 correspond to the running resistance calculating means.

In step 11, the throttle valve opening degree TVO corresponding to the current vehicle speed VSP on the downshift line from the next shift stage (4 speeds) to the current shift stage (3 speeds) in the shift pattern diagram is obtained. _{It is defined as DWN} (down shift throttle opening degree in the next shift stage).

That is, as shown in FIG. 12, the throttle opening degree of point D on the downshift line of 4 speeds → 3 speeds at the vehicle speed VSP ₁ is the same as point C which is the point of occurrence of an upshift request of 3 speeds → 4 speeds. Obtain TVO _DWN .

In step 12, turbine torque Tt _NGP is calculated based on the downshift throttle opening degree TVO _DWN and the current turbine rotation speed Nt at the next shift stage (4 speeds) with reference to the analysis diagram shown in FIG.

In step 13, on the basis of the calculated turbine torque Tt _NGP , the driving force (maximum driving force after shifting) F2 at the next shift speed (4 speeds) is calculated by the following equation.

F2 = Tt _NGP XNG _RATIO XK

In addition, NG _RATIO is an integer determined according to gear ratio K, tire radius, etc. of the next gear stage (4 speeds).

Here, the steps 11-13 correspond to the second driving force calculating means.

In step 14, the maximum driving force F2 at the next shift stage (4 speeds) is compared with the running resistance RESI _ALL .

As a result of the comparison, in the case of F2? RESI _ALL , the process proceeds to step 15 to permit the upshift and advances the shift to the next shift stage (4 speeds).

In contrast, in the case of F2 &lt; RESI _ALL , the process proceeds to step 16, where up-shifting is prohibited and held at the current shift stage (3 speeds). When the upshift is prohibited, instead of maintaining the current shift stage, the upshift line from the current shift stage to the next shift stage in the shift pattern diagram may be moved to the high vehicle speed side.

Here, step 14 corresponds to the comparison means, and step 16 corresponds to the upshift inhibiting means.

Next, the shift control routine of FIG. 7 which is an embodiment corresponding to the second invention will be described. In addition, FIG. 7 follows FIG. 5, which is executed in place of FIG. 6, and is executed after execution of steps 1 to 10 of FIG.

In step 21, a predetermined value AFL is added to the current throttle valve opening degree TVO to obtain an additional throttle opening degree TVO _AFL at the next shift stage (4 speeds) as follows.

TVO _AFL = TVO + AFL

In step 22, the turbine torque Tt _NGP is calculated based on the additional throttle opening degree TVO _AFL and the current turbine rotation speed Nt at the next shift stage (4 speeds) with reference to the drawing shown in FIG.

In step 23, on the basis of the calculated turbine torque Tt _NGP , the driving force (additional driving force after shift) F3 at the next shift stage (4 speeds) is calculated according to the following equation.

F3 = Tt _NGP X NG _RATIO XK

In addition, NG _RATIO is a gear ratio of the next speed change stage (4 speeds), K is an integer determined according to a tire radius, and the like.

Here, the steps 21-23 correspond to the third driving force calculating means.

In step 24, the additional driving force F3 at the next shift stage (4 speeds) is compared with the running resistance RESI _ALL .

As a result of the comparison, in the case of F3? RESI _ALL , the process advances to step 25 to permit the upshift and advance the upshift to the next shift stage (4 speeds).

In contrast, in the case of F3 &lt; RESI _ALL , the process proceeds to step 26 where up-shifting is prohibited and held at the current shift stage (3 speeds).

Here, step 24 corresponds to the comparison means, and step 26 corresponds to the upshift inhibiting means.

Next, the shift control routine of FIG. 8 which is an embodiment corresponding to the third invention will be described. In addition, FIG. 8 is followed by FIG. 5 and is executed in place of FIG. 6, and is executed after execution of steps 1 to 10 of FIG.

In step 31, the throttle valve opening degree TVO corresponding to the current vehicle speed VSP on the downshift line from the next shift stage (4 speeds) to the current shift stage (3 speeds) in the shift pattern diagram is obtained. _{Let DWN} (downshift throttle opening in the next shift stage) be.

That is, as shown in Fig. 12, the throttle opening degree of the D point on the downshift line of 4 speeds → 3 speeds at the vehicle speed VSP1 is the same as the point C of occurrence of the upshift request of 3 speeds to 4 speeds TVO _DWN. Obtain

In step 32, referring to the analysis diagram shown in FIG. 10, the turbine torque Tt _NGP is calculated based on the downshift throttle opening degree TVO _DWN and the current turbine rotation speed Nt at the next shift stage (4 speeds).

In step 33, on the basis of the calculated turbine torque Tt _NGP , the driving force (maximum driving force after shifting) F2 at the next shift stage (4 speeds) is calculated from the following equation.

F2 = Tt _NGP X NG _RATIO XK

In addition, NG _RATIO is a gear ratio of the next speed change stage (4 speeds), K is an integer determined according to a tire radius, and the like.

Here, the part of steps 31-33 corresponds to the second driving force calculating means.

In step 34, referring to the analysis diagram shown in FIG. 10, the turbine torque Tt _NGP 'is calculated based on the current throttle valve opening degree TVO and the turbine rotational speed Nt.

In step 35, based on the calculated turbine torque Tt _NGP ', the driving force (actual driving force after shifting) F4 at the next shift stage (4 speeds) is calculated according to the following equation.

F4 = Tt _NGP '' X NG _RATIO XK

In addition, NG _RATIO is a gear ratio of the next speed change stage (4 speeds), K is an integer determined according to a tire radius, and the like.

Here, the parts of steps 34 and 35 correspond to the fourth driving force calculating means.

In step 36, the maximum drive force F2 at the next shift stage (4 speeds) and the actual drive force F4 at the next shift stage (4 speeds) are averaged, and a predetermined value AFL is added to the next shift stage, as follows. Calculate the driving force (additional driving force after shifting) F5 at (4 speeds).

F5 = (F2 + F4) / 2 + AFL

In step 37, the additional driving force F5 at the next shift stage (4 speeds) is compared with the running resistance RESI _ALL .

As a result of the comparison, in the case of F5? RESI _ALL, the flow advances to step 38 to allow the upshift and advances to the next shift stage (4 speeds).

On the other hand, in the case of F5 &lt; RESI _ALL , the process proceeds to step 39 and the upshift is prohibited and held at the current shift stage (3 speeds).

Here, step 37 corresponds to the comparison means, and step 39 corresponds to the upshift inhibiting means.

As described above, according to the first invention, the driving force (maximum driving force after shifting) at another shift stage is calculated based on the engine load corresponding to the current vehicle speed on the downshift line of the other shift stage in the shift pattern diagram. In order to judge whether or not upshift is prohibited by comparing this with the running resistance, it is possible to more appropriately perform the upshift prohibition control at the time of driving uphill, so that the shift hunting can be prevented and the fuel cost and driving performance can be improved. I can get the effect.

Further, according to the second invention, the driving force (additional driving force after shifting) at another shift stage is calculated based on a value obtained by adding a predetermined value to the current engine load, and comparing this with the running resistance to prohibit the upshift. Since it judges whether or not, the effect similar to 1st invention is acquired.

According to the third aspect of the present invention, the driving force (maximum driving force after shifting) at the other shift stage is calculated based on the engine load corresponding to the current vehicle speed on the downshift line of the other shift stage in the shift pattern diagram. The driving force at the other shift stage (actual driving force after shifting) is calculated based on the current engine load, and the driving force at the other shift stage (additional driving force after shifting) is calculated based on the result of the calculation. Compared with the resistance, it is judged whether the upshift is prohibited or not, and therefore, almost the same effect as in the first invention can be obtained.

Claims (9)

A vehicle speed detecting means for detecting a vehicle speed, an engine load detecting means for detecting an engine load, a shift stage selecting means for selecting a shift stage of the transmission with reference to a shift pattern diagram based on the detected vehicle speed and engine load; A shift control apparatus for an automatic transmission of an automobile provided with a shift command means for generating an upshift request or a downshift request based on the selection result, wherein the driving force at the current shift stage is calculated based on the current engine load. A first driving force calculating means, a traveling resistance calculating means for calculating a traveling resistance on the basis of at least the calculation result of the first driving force calculating means, and downshifting the driving force at another shifting stage in another shifting stage in the shift pattern diagram Second driving force calculating means calculated on the basis of an engine load corresponding to a current vehicle speed on board; Comparing means for comparing the calculation result of the resistance calculation means and the calculation result of the second driving force calculation means, and the calculation result of the second driving force calculation means is calculated as the calculation result of the running resistance calculation means, in accordance with the comparison result of the comparison means. The shift control apparatus of the automatic transmission characterized by providing the upshift prohibition means which prohibits the upshift to another shift stage, when smaller. 2. The shift control apparatus of an automatic transmission according to claim 1, wherein the upshift prohibiting means maintains a current shift stage. The shift control apparatus for an automatic transmission according to claim 1, wherein the upshift prohibiting means moves an upshift line from the current shift stage to another shift stage in the shift pattern diagram. Vehicle speed detecting means for detecting a vehicle speed, engine load detecting means for detecting an engine load, shift stage selecting means for selecting a shift stage of a transmission based on the detected vehicle speed and the engine load with reference to a shift pattern diagram; A shift control apparatus for an automatic transmission of an automobile provided with a shift command means for generating an upshift request or a downshift request based on the selection result, wherein the driving force at the current shift stage is calculated based on the current engine load. The first driving force calculating means, the driving resistance calculating means for calculating the traveling resistance based on at least the calculation result of the first driving force calculating means, and the driving force at another shift stage is added to a value obtained by adding a predetermined value to the current engine load. Third driving force calculation means calculated on the basis of the calculation result, calculation results of the travel resistance calculation means and calculation results of the third driving force calculation means An upshift for prohibiting an upshift to another shift stage when the calculation result of the third driving force calculation means is smaller than the calculation result of the travel resistance calculation means according to the comparison means for comparing and the comparison result of the comparison means A shift control apparatus for an automatic transmission, characterized by providing a prohibition means. 5. The shift control apparatus of an automatic transmission according to claim 4, wherein the upshift prohibiting means maintains a current shift stage. 5. The shift control apparatus of an automatic transmission according to claim 4, wherein the upshift prohibiting means moves an upshift line from the current shift stage to another shift stage in the shift pattern diagram. A vehicle speed detecting means for detecting a vehicle speed, an engine load detecting means for detecting an engine load, a shift stage selecting means for selecting a shift stage of the transmission based on the detected vehicle speed and the engine load with reference to a shift pattern diagram; A shift control apparatus for an automatic transmission of a vehicle having a shift command means for generating an upshift request or a downshift request based on the selection result, wherein the driving force at the current shift stage is based on the current engine load. The first driving force calculating means for calculating, the driving resistance calculating means for calculating the traveling resistance based on at least the calculation result of the first driving force calculating means, and the driving force in the other shifting stages of the other shifting stages in the shift pattern diagram; Second driving force calculating means calculated on the basis of the engine load corresponding to the current vehicle speed on the shift line; The fourth driving force calculating means for calculating the driving force at the high speed based on the current engine load, the calculation result of the second driving force calculating means, and the calculation result of the fourth driving force calculating means, A fifth driving force calculation means for calculating a driving force, comparison means for comparing the calculation result of the traveling resistance calculation means and the calculation result of the fifth driving force calculation means, and the fifth driving force calculation according to the comparison result of the comparison means. And an upshift prohibiting means for prohibiting an upshift to another shift stage when the calculation result of the means is smaller than the calculation result of the travel resistance calculation means. 8. The shift control apparatus of an automatic transmission according to claim 7, wherein the upshift inhibiting means maintains a current shift stage. 8. The shift control apparatus of an automatic transmission according to claim 7, wherein the upshift prohibiting means moves the upshift line from the current shift stage to another shift stage in the shift pattern diagram.