JPH0374532A - Vehicle travel control device - Google Patents

Abstract

PURPOSE:To control fluctuations in output of an engine low to improve fuel cost and suppress the rise in exhaust gas temperature by judging the bad road traveling state of a vehicle, and restricting the amount of output control of the engine at the time of changing the speed to be reduced when the road is judged to be bad. CONSTITUTION:When an automatic transmission (a) is actuated, output of an engine (c) is controlled through an output control means (b). In such a vehicle, the degree of irregularity of the road surface is detected by a bad road state judging means (d). When the bad road traveling state of the vehicle is detected by the bad road judging means (d), the amount of output control controlled by the output control means (b) is restricted to be reduced by an output control restricting means (e). Thus, when the vehicle travels on a bad road, fluctuations in the output of the engine are controlled to be low so as to achieve the improvement of fuel cost and the suppression of the rise in exhaust gas temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a driving control device for a vehicle equipped with an automatic transmission, and more particularly to a driving control device for a vehicle in which engine output control is performed during gear shifting.

Conventional technology As a transmission installed in a conventional vehicle, for example,
There is an automatic transmission as disclosed in Japanese Patent No. 2-62047, in which a plurality of hydraulically operated friction elements (clutches, brakes, etc.) incorporated in a gear train are engaged and released as appropriate. This makes it possible to obtain a plurality of gears.

By the way, when an automatic transmission is shifted in this way,
A newly engaged friction element generates shift shock, which worsens the ride comfort of the vehicle, so various methods have been proposed in the past that reduce the shock by controlling the engagement pressure of the friction element during gear shifts. However, in recent years, an automatic transmission has been proposed in which the shift shock of an automatic transmission is further effectively reduced by controlling the engine output (reducing the output) (see Japanese Patent Laid-Open No. 62-99225).

Problems to be Solved by the Invention However, in such conventional vehicles, controlling engine output during gear shifting can have a significant effect in reducing gear shift shock; When trying to perform this, it is necessary to perform the output control frequently and to increase the control amount, which inevitably leads to problems such as deterioration of fuel efficiency and increase in engine exhaust temperature.

In view of such conventional problems, the present invention has been developed to provide a vehicle driving control device that limits the amount of engine output control during gear shifting in a driving state in which a gear shifting shock does not affect the occupant in the front column, that is, while driving on a rough road. The purpose is to provide

Means for Solving the Problems In order to achieve the above object, the present invention provides a vehicle in which the output of the engine C is controlled via the output control means when changing the speed of the automatic transmission a, as shown in FIG. a rough road condition determining means d for detecting the degree of unevenness of the road surface; and an output control limiting means e for reducing the output control amount by the output control means when the rough road condition determining means d detects a rough road driving condition. It is constructed by providing the following.

Effects With the above-described configuration, the vehicle running control device of the present invention is provided with a rough road condition determining means d to determine the rough road traveling condition, and when driving on the rough road, the output control limiting means e is used to control the speed change. Since the output control amount of engine C is reduced, on rough roads with large vehicle body vibrations, there is no effect on the front pillar even if the shift shock reduction is sacrificed, and by limiting engine output control in this way, The influence of output fluctuations can be reduced.

Example Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

That is, FIG. 2 shows an embodiment of the vehicle travel control system of the present invention, in which 10 is an engine, 12 is an automatic transmission, and the output rotation of the engine 10 is transferred to the automatic transmission via an l/lux converter 14. The input engine rotation is appropriately changed in speed by the automatic transmission 12 and transmitted to drive wheels (not shown).

The ignition timing of the engine 10 is controlled by an ignition advance device 16, and the ignition angle device 16 is operated by a control signal output from an engine control unit 200.

On the other hand, as shown in FIG. 3, the automatic transmission 12 has a gear train including a first planetary gear set PC and a second planetary gear set P(it).

Above 1. The second planetary gear sets PC, PG are each configured as a simple planetary gear, and the first... 2nd Sangiya S...
S, and the first. 2nd pinion gear P,,P.

And the first. second ring gears R, , R, and first ring gears R, , R,; It is constituted by second binion carriers PC, , PC, and.

Also, the above 1. As shown in the figure, the gear train composed of the second planetary gear sets PG, PC, includes a reverse clutch R/C connecting the input shaft 1/S and the first sun gear SL, and a reverse clutch R/C connecting the input shaft 1/S and the first sun gear SL. High clutch H/C connecting pinion carrier PC,
, a forward clutch F/C connecting the first pinion carrier PCI and the second ring gear R2.

A band brake B/B that fixes the first sun gear S to the casing C/S side and a low and reverse brake L&R/B that fixes the first pinion carrier Pct to the casing C/S side are provided.

Further, a forward one-way clutch F10/C is connected between the forward clutch F/C and the second ring gear R7.
is provided, and a row one-way clutch L10 is provided between the first pinion carrier PC8 and the casing C/S.
・C is provided, and an overrun clutch 0- is provided between the first pinion carrier PCI and the second ring gear R in parallel with the forward one-way clutch F10・C.
R/C is placed.

Furthermore, 10 revolutions of the engine are input to the input shaft 1/S in FIG. 4 through the torque converter 14.

By the way, in the main transmission 12, as shown in Table 1 below, each friction element (R/C, H/C, F/C, B/B.

L&R/B) are engaged and released by the shift hydraulic pressure supplied from the hydraulic pressure control valve 18, so that various gears can be obtained.

The hydraulic pressure control valve 18 is driven by a speed change signal output from the A/T control unit 202 based on, for example, a shift schedule shown in FIG.

Note that the throttle opening signal detected by the throttle opening sensor 204 and the vehicle speed signal detected by the vehicle speed sensor 206 are input to the input/T control unit 202, and based on these signals, the current setting is determined from the shift schedule. The gear position to be changed is determined as shown in the table below.

In the table, an O mark indicates a fastened state, and no mark indicates a released state.

Further, the forward one-way clutch F10-C is free when the second ring gear R2 rotates in the forward direction relative to the first pinion carrier PC8, and is locked when the second ring gear R2 rotates in the reverse direction.
0-C is free when the first pinion carrier PC rotates in the forward direction, and is locked when it rotates in the reverse direction.

Furthermore, although the above-mentioned overrun clutch 0-R/C is not shown in Table 1, the overrun clutch 0-R/C
When the accelerator opening is engaged at a low speed of 3rd gear or lower and the opening degree is 1/16 or less, the function of the forward one-way clutch F10-C is eliminated and the engine brake is operated.

Incidentally, the engine control unit 200 is provided with an output control means 208, which inputs the gear shift signal output from the A/T control unit 202 and retards the ignition advance device 16 when the automatic transmission 12 shifts. So-called traction control is performed in which a signal is output to reduce the output torque of the engine 10.

That is, by lowering the engine output during gear shifting of the automatic transmission 12 in this manner, gear shifting shock caused by engagement shock of the friction element is reduced.

Note that the means for reducing the engine output is not limited to the above-mentioned ignition retard, but can also be achieved by controlling the fuel injection amount.

By the way, the above-mentioned vehicle running control device is equipped with an ultrasonic road sonar 210 as means for determining rough road conditions, and the road surface conditions detected by the ultrasonic road sonar 210 are outputted to a shock ab controller 212 to control the suspension (not shown). The damping force of the shock absorber is variably controlled.

Here, in this embodiment, the engine control unit 200 is provided with an output control limiting means 214 that inputs a detection signal from the ultrasonic road sonar 210, and when it is determined that the road surface condition is a bad road, the output control Limiting means 21
4 outputs a signal to the output control means 208 to reduce the amount of retard of the ignition advance device 16.

With the above configuration, the functions of the vehicle travel control device of this embodiment will be explained with reference to the flowchart of FIG. 5.

That is, the above flowchart is executed for a predetermined short time (for example, l
First, the throttle opening degree and vehicle speed are read in step I, and the detection signal of the ultrasonic road sonar 210 is read in the next step (2).

Then, in the next step ■, the ultrasonic road sonar 21
It is determined whether or not the vehicle is traveling on a rough road based on the detection signal of 0. If rNOJ is determined in step (2), that is, if it is determined that the road is flat, the process proceeds to step (2), and the output control means 208 turns on the ignition. While determining the output control amount (retard amount) at the time of gear change output to the advance angle device 16 to the normal state,
If rYEsJ is determined in the above step (2), that is, if it is determined that the road is rough, the process proceeds to step V, and the output control amount during gear shifting is determined to be the control state for the rough road, that is, to reduce the retard amount.

After the processing in Steps, B, or V above is executed, the process proceeds to Step ■, and based on the throttle opening degree and vehicle speed read in Step I, it is determined whether or not the gear is being shifted based on the shift schedule shown in Fig. 4. is judged.

If it is determined that the gear is being shifted and rYES in the above step (2), the process proceeds to step (2), and the output control amount determined in the above step (2) or step V is transferred to the output control means 20.
8 to the ignition advance device 16, the engine output is reduced by a large amount of retard on a flat road, and the reduction in engine output is suppressed by a small amount of retard on a rough road.

On the other hand, if it is determined that rNOJ is determined in step (2) above, the process proceeds to step (2), and the ignition advance device 1
It outputs the ignition advance control signal which is output to 6.

Therefore, in this embodiment, when changing gears while driving on a rough road, the ignition retard amount controlled by the output control means 208 is suppressed by the output control limiting means 214, so that the engine 1
The range of output fluctuation is reduced, which improves fuel efficiency and suppresses increases in exhaust temperature.

In addition, when reducing the fuel injection amount instead of using the ignition retard as the output control means for the engine 10, the amount of decrease in the fuel injection amount may be reduced when driving on a rough road.

Furthermore, in the above embodiment, a case was disclosed in which the ignition retard amount at the time of shifting is controlled to be small when driving on a rough road.
The present invention is not limited to this, and the frequency of output control of the engine 10 may be suppressed when driving on a rough road.

As described in detail, the vehicle running control device of the present invention includes a rough road condition determining means in a vehicle in which the output of the engine is controlled via the output control means when changing gears of the automatic transmission. When the vehicle is traveling on a rough road, the engine output control amount is reduced through the output control limiting means when the vehicle is changing gears, so that fluctuations in the engine output are suppressed to a small level when the vehicle is traveling on the rough road. be able to.

Therefore, even if the engine output control amount during gear shifting is reduced in this way, the front pillar will not be affected by gear shifting shock due to large vehicle body vibrations on rough roads, improving fuel efficiency by suppressing engine output fluctuations, and improving engine efficiency. This has the excellent effect of suppressing a rise in exhaust gas temperature.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the concept of the present invention, FIG. 2 is a schematic diagram showing an embodiment of the present invention, FIG. 3 is a schematic diagram showing a gear train of an automatic transmission used in the present invention, and FIG. FIG. 4 is an explanatory diagram showing a shift schedule of an automatic transmission used in the present invention, and FIG. 5 is a flowchart showing an example of processing for controlling the present invention. 10...Engine, 12...Automatic transmission, 16...
・Ignition advance device, 18...hydraulic pressure control valve,
200... carrot control unit, 202...
. . . A/T control unit, 208 . . . Output control means, 210 . . . Ultrasonic road sonar (bad road condition judgment means), 214 . 3 people Figure 1 Figure 5

Claims (1)

[Claims] (1) In a vehicle in which the output of the engine is controlled via the output control means when shifting the automatic transmission, a rough road condition determining means detects the degree of unevenness of the road surface, and the rough road condition determining means detects the rough road driving condition. When detected,
A vehicle running control device comprising: output control limiting means for reducing the amount of output control by the output control means.