JPH07167284A - Control device for automatic transmission - Google Patents

Abstract

PURPOSE:To control the catalyst temperature to the optimum value without deteriorating emission by changing the stored shift schedule to the shift schedule increasing (decreasing) the engine revolving speed when the catalyst temperature is lower (higher) than the prescribed target value. CONSTITUTION:Detected signals from various sensors such as a throttle opening detecting sensor 20, a vehicle speed sensor 22, an engine revolving speed sensor 24, an intake air quantity sensor 26, an exhaust gas temperature sensor 28, and an air-fuel ratio sensor 30 are inputted to an electronic control unit(ECU) operating and controlling an engine control device 16 and a gear stage control device 14 in response to the operation state such as the ignition timing and fuel injection quantity of an engine 10. The control schedule is set from the shift schedule in a ROM 18b based on the operation state detected by various sensors. The gear stage and lock-up state of an automatic transmission 12 are changed by the control signal shift control-processed according to the high or low catalyst temperature and outputted to the gear stage control device 14. The exhaust gas purifying catalyst temperature can be controlled at the optimum value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission control device for changing a gear stage and a lockup state of an automatic transmission according to a driving state of a vehicle.

[0002]

2. Description of the Related Art Conventionally, in an internal combustion engine for a vehicle, hydrocarbons (HC) and carbon monoxide (C) in exhaust gas have been used.
In order to purify O) and nitric oxide (NOx), a catalytic converter is provided in the exhaust passage.

[0003] Here, the efficiency of exhaust gas purification of the catalyst installed in the catalytic converter decreases when it goes out of a predetermined temperature range. This characteristic is particularly remarkable in the so-called lean NOx catalyst that reduces NOx in exhaust gas in the presence of HC. That is, this lean NOx catalyst is used in a so-called lean burn system that controls the air-fuel ratio in the vicinity of when the amount of NOx in the exhaust gas exceeds the peak and HC increases, and the NOx purification rate at high temperature ( For example, 4
Even at 50 ° C or higher) at low temperature (for example, 300 ° C or lower)
But it drops sharply. Therefore, particularly when a lean NOx catalyst is used, it is necessary to maintain the temperature of the catalyst within a range where the NOx purification rate is high.

Therefore, conventionally, such lean NOx has been used.
For an internal combustion engine using a catalyst, for example, Japanese Patent Laid-Open No.
As disclosed in Japanese Patent Laid-Open No. 54343/1993, the air-fuel ratio is adjusted according to the exhaust gas temperature and the exhaust gas recirculation device (EG
A device for controlling the catalyst temperature to an optimum value by operating R) has been proposed.

Further, as disclosed in Japanese Utility Model Laid-Open No. 3-83314, there is also provided a device for adjusting the catalyst temperature by providing a cooling chamber in the catalytic converter and controlling the circulation speed of the fluid circulated in the cooling chamber. Proposed.

[0006]

However, in the former device, since the air-fuel ratio and the amount of circulation of exhaust gas to the intake passage are changed, there is a problem that emission is deteriorated. .

On the other hand, in the latter device, the cooling fluid must be circulated at a high temperature, so that the device becomes complicated and the cost is significantly increased. Even with a normal three-way catalyst, since the purification rate of exhaust gas decreases at low temperatures, it is significant to actively control the catalyst temperature, and the above-mentioned problems similarly occur.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide an automatic transmission control device capable of controlling the temperature of a catalyst to an optimum value at a low cost without deteriorating the emission. To aim.

[0009]

[Means for Solving the Problems] That is, the present invention according to claim 1 made in order to achieve the above object,
As illustrated in (A), a driving state detecting means for detecting a driving state of a vehicle equipped with an internal combustion engine and an automatic transmission, and a gear shifting state of the automatic transmission corresponding to the driving state of the vehicle. A storage unit that stores a shift schedule in advance, and a shift control unit that controls the shift state of the automatic transmission based on the shift schedule stored in the storage unit and the driving state of the vehicle detected by the driving state detection unit. And a catalyst temperature detecting means for detecting a temperature of a catalyst installed in a catalytic converter provided in an exhaust passage of the internal combustion engine, and a catalyst detected by the catalyst temperature detecting means. When the temperature of the internal combustion engine is lower than a predetermined target value, the shift schedule used by the shift control means is changed to a shift schedule in which the rotation speed of the internal combustion engine is increased. When the detected catalyst temperature is higher than a predetermined target value, the shift schedule used by the shift control means is changed to a shift schedule in which the rotation speed of the internal combustion engine becomes low. The gist is an automatic transmission control device including a changing unit.

The present invention according to claim 2 is based on FIG.
As illustrated in (B), a driving state detecting means for detecting a driving state of a vehicle equipped with an internal combustion engine and an automatic transmission, and a gear shifting state of the automatic transmission corresponding to the driving state of the vehicle. A storage unit that stores a shift schedule in advance, and a shift control unit that controls the shift state of the automatic transmission based on the shift schedule stored in the storage unit and the driving state of the vehicle detected by the driving state detection unit. And a catalyst temperature detecting means for detecting a temperature of a catalyst installed in a catalytic converter provided in an exhaust passage of the internal combustion engine, and a catalyst detected by the catalyst temperature detecting means. Is lower than a predetermined target value, the operating state of the vehicle detected by the operating state detecting means and used by the shift control means is set to the internal combustion engine. Is output to the shift control means after being corrected so that the rotation speed becomes higher, and when the detected temperature of the catalyst is higher than a predetermined target value, the shift control is detected by the operating state detecting means. Means for correcting the operating state of the vehicle used by the means so as to reduce the rotational speed of the internal combustion engine and outputting the corrected operating state to the shift control means. Is the gist.

According to a third aspect of the present invention, in the automatic transmission control device according to the first and second aspects, the catalyst temperature detecting means controls the temperature of the catalyst based on the operating state of the vehicle. The gist is an automatic transmission control device characterized in that the temperature of the catalyst is detected by estimating

[0012]

In the automatic transmission control device according to claim 1 configured as described above, the operating state detecting means detects the operating state of the vehicle equipped with the internal combustion engine and the automatic transmission. The storage means stores in advance a shift schedule for determining the shift state of the automatic transmission in accordance with the driving state of the vehicle. Then, the shift control means, based on the shift schedule stored in the storage means and the driving state of the vehicle detected by the driving state detection means,
Controls the speed change state of the automatic transmission.

Here, in the automatic transmission control device according to the first aspect, the catalyst temperature detecting means detects the temperature of the catalyst incorporated in the catalytic converter provided in the exhaust passage of the internal combustion engine, and the shift schedule. When the temperature of the catalyst detected by the catalyst temperature detecting means is lower than the predetermined target value, the changing means changes the shift schedule used by the shift control means to a shift schedule in which the rotation speed of the internal combustion engine becomes high. If the temperature of the catalyst detected by the catalyst temperature detection means is higher than the predetermined target value, the shift schedule used by the shift control means is changed to a shift schedule in which the rotation speed of the internal combustion engine becomes low. To do.

Therefore, according to the automatic transmission control device of the first aspect, even when the operating state of the vehicle is the same, when the temperature of the catalyst installed in the catalytic converter is lower than the predetermined target value. Controls the shift state of the automatic transmission so that the rotation speed of the internal combustion engine increases, and conversely, when the temperature of the catalyst is higher than a predetermined target value, the rotation speed of the internal combustion engine decreases. The shift state of the automatic transmission is controlled.

Therefore, according to the automatic transmission control device of the first aspect, when the temperature of the catalyst is lower than the target value, the thermal energy discharged from the exhaust passage of the internal combustion engine is increased to increase the catalyst temperature. Can raise the temperature, and vice versa
When the temperature of the catalyst is higher than the target value, it is possible to reduce the exhaust gas energy and lower the temperature of the catalyst. The exhaust gas purification rate can be maintained at a high level.

Further, in the automatic transmission control device according to a second aspect of the present invention, similarly to the automatic transmission control device according to the first aspect, the shift control means includes the shift schedule and the operating state stored in the storage means. The shift state of the automatic transmission is controlled based on the vehicle operating state detected by the detecting means.However, the operating state correcting means determines that the catalyst temperature detected by the catalyst temperature detecting means is lower than a predetermined target value. Is also low, the driving state of the vehicle detected by the driving state detection means and used by the shift control means is corrected so as to increase the rotation speed of the internal combustion engine and output to the shift control means. When the temperature of the catalyst detected by the catalyst temperature detecting means is higher than a predetermined target value, the operating state of the vehicle detected by the operating state detecting means and used by the shift control means is changed to the internal combustion engine. Speed is outputted to the correction to the shift control means so as to be lower.

That is, in the automatic transmission control device according to the first aspect, the rotation speed of the internal combustion engine is changed by changing the shift schedule used by the shift control means. In the automatic transmission control device described above, by correcting the operating state detected by the operating state detecting means and used by the shifting control means, even if the operating state is the same, the temperature of the catalyst has a predetermined target value. When the temperature is lower than the value, the speed change state of the automatic transmission is controlled so that the number of rotations of the internal combustion engine is high. Conversely, when the temperature of the catalyst is higher than a predetermined target value, the rotation speed of the internal combustion engine is increased. The speed change state of the automatic transmission is controlled so that the number becomes low.

Therefore, even with the automatic transmission control device according to the second aspect, the emission is not deteriorated,
Moreover, the catalyst temperature can be brought close to a predetermined target value at low cost, and the exhaust gas purification rate can be maintained at a high level. Here, in the automatic transmission control device according to the third aspect, the catalyst temperature detecting means in the automatic transmission control device according to the first and second aspects determines the temperature of the catalyst based on the operating state of the vehicle. By estimating,
The temperature of the catalyst is detected.

Therefore, according to the automatic transmission control device of the third aspect, the temperature of the catalyst can be brought close to the predetermined target value without additionally providing a temperature sensor or the like for directly detecting the temperature of the catalyst. it can.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 2 is a schematic configuration diagram showing an automatic transmission control device of the first embodiment. The automatic transmission control device according to the present embodiment is a gear position control device that changes a gear position and a lockup state of an automatic transmission 12 that shifts and transmits a drive output of an engine 10 mounted on a vehicle to drive wheels (not shown). 14
And a well-known CPU 18a, ROM 18b, RAM 18c
And an electronic control unit (hereinafter referred to as ECU) 18 that controls the operation of the engine control unit 16 and the gear stage control unit 14 that control the ignition timing and the fuel injection amount of the engine 10 according to the operating state. , Are provided.

The ECU 18 has a throttle sensor 20 for detecting the throttle opening, a vehicle speed sensor 22 for detecting the vehicle speed, and a rotation speed sensor 2 for detecting the engine speed.
4, an intake air amount sensor 26 that detects the amount of air taken into the engine 10 (intake air amount), an exhaust temperature sensor 28 that detects the exhaust temperature, and an air-fuel ratio sensor 3 that detects the air-fuel ratio
Detection signals from various sensors, such as 0, for detecting the driving state of the vehicle are input.

In the automatic transmission control device of this embodiment having the above-mentioned configuration, the ECU 18 (CPU 18a) is
By executing a shift schedule setting process which will be described later, the operating state of the vehicle is detected based on the detection signals from the various sensors, and based on the detection result, a plurality of shift schedules stored in the ROM 18b serving as a storage unit are detected. The shift schedule actually used for shift control is set from the inside. Then, by executing a shift control process to be described later, a control signal is output to the gear stage control device 14 based on the set shift schedule and the detected operating state to shift control of the automatic transmission 12 (gear stage and Change the lockup status).

First, the shift schedule stored in the ROM 18b will be described with reference to FIG. As shown in FIG. 3, the shift schedule of the present embodiment is stored as a two-dimensional data map having vehicle speed V and throttle opening θ as parameters. Further, in this embodiment, a normal gear shift schedule consisting of gear change points indicated by solid lines 2N, 3N, 4N and lock-up points indicated by dotted lines 2LN, 3LN, 4LN and dashed-dotted lines 2C, 3C, 4C are shown. A gear shift schedule for cooling, which includes gear change points and lock-up points indicated by dashed-dotted lines 2LC, 3LC, and 4LC, and a dashed-dotted line 2H,
3H and 4H gear change points and chain double-dashed line 2
Three types of shift schedules, that is, a warm-up shift schedule including lock-up points indicated by LH, 3LH, and 4LH, are prepared in advance, and are selectively selected by a shift schedule setting process described later.

Note that 2N, 2C, and 2H indicate the change points from the 1st speed gear to the 2nd speed gear, respectively, and 3N, 3C, 3H.
H indicates a change point from the second speed gear to the third speed gear, and 4N, 4C, 4H indicates a change point from the third speed gear to the fourth speed gear, respectively. On the other hand, 2LN, 2L
C and 2LH indicate lockup points in the second gear, 3LN, 3LC and 3LH respectively indicate lockup points in the third gear, 4LN, 4LC and 4LN.
LH indicates the lockup point in the fourth gear, respectively. And 3LN, 3LC, 3LH and 4LN,
The boundaries with 4LC and 4LH are points at which they change points 4N, 4C and 4H, respectively.

For each shift schedule, the case where the throttle opening θ is constant and the vehicle speed V gradually increases is taken as an example. When the normal shift schedule is set as shown in FIG. In the case where the cooling shift schedule is set, the speed is changed to the higher gear speed faster than before, and the gears are locked up faster. On the contrary, when the warm-up shift schedule is set, the gear speed is changed to a higher gear speed later than when the normal shift schedule is set, and each gear is slower. You will be locked up in steps.

In other words, even if the operating conditions of the vehicle are the same, when the cooling shift schedule is set, the engine 1
The number of revolutions of 0 is suppressed low, and conversely, when the warm-up shift schedule is set, the number of revolutions of the engine 10 is increased. Next, the shift control process executed by the ECU 18 will be described with reference to FIG. still,
This shift control process is repeatedly executed as an interrupt process at predetermined time intervals when the ignition switch (not shown) is turned on and the ECU 18 is powered on.

As shown in FIG. 4, when the shift control process is started, first, step (hereinafter, simply referred to as S) 1
At 10, the vehicle speed and the throttle opening are detected based on the detection signals from the vehicle speed sensor 22 and the throttle sensor 20, and the gear state of the automatic transmission 12 (current gear stage).
And the lock-up state (whether or not the lock-up is currently performed and the gear stage if the lock-up is present) are detected from the control state of the gear stage control device 14, and a process as an operating state detecting means is executed.

Then, in the following S120, among the three types of shift schedules shown in FIG. 3, the shift schedule set by the shift schedule setting process described later,
By applying the vehicle speed and the throttle opening detected in S110, the control gear state (gear stage to be changed) and the control lockup state (whether or not to lockup and if so, that gear stage) are calculated. .

Then, in the following S130, it is determined whether or not the gear state detected in S110 is the same as the control gear state calculated in S120. If it is determined to be the same, the process proceeds to S140. That is, if the current gear is the same as the gear to be changed, it is not necessary to change the gear and the process proceeds to S140.

In step S140, it is determined whether the lockup state detected in step S110 is the same as the control lockup state calculated in step S120. The shift control process ends. That is, when the lock-up is not currently performed and the control lock-up state calculated in S120 is not locked up, or the lock-up is currently performed in one of the gears, and the gear is in S120. If it is the same as the gear position indicated by the control lock-up state calculated in step 3, the process is terminated because it is not necessary to change the lock-up state.

If it is determined in S140 that the lockup state detected in S110 is not the same as the control lockup state calculated in S120, S160.
Then, the process as the shift control means for outputting a control signal to the gear stage control device 14 so as to switch the lock-up state of the automatic transmission 12 to the state indicated by the control lock-up state is executed. This shift control process ends.

On the other hand, when it is determined in S130 that the gear state detected in S110 is not the same as the control gear state calculated in S120, the process proceeds to S135 to release the lockup, and then to S150. Then, a process as a gear shift control means for outputting a control signal to the gear stage control device 14 so as to switch the gear stage of the automatic transmission 12 to the gear stage indicated by the control gear state is performed, and thereafter, this gear shift control process To finish.

Then, in this way, S150 or S16
When the control signal is output in the processing of 0, the gear stage control device 14 changes the shift state of the automatic transmission 12 based on the control signal. Next, the shift schedule setting process executed by the ECU 18 will be described with reference to FIG. As described above, this shift schedule setting process is executed to selectively set the shift schedule used in S120 of the shift control process from the three types of shift schedules shown in FIG. Similarly to the shift control process, when the ECU 18 is powered on, it is repeatedly executed at predetermined time intervals.

As shown in FIG. 5, when the shift schedule setting process is started, first, at S210, the exhaust temperature,
The air-fuel ratio, the intake air amount, and the vehicle speed are detected based on the detection signals from the exhaust temperature sensor 28, the air-fuel ratio sensor 30, the intake air amount sensor 26, and the vehicle speed sensor 22, respectively.

Then, in subsequent S220, the engine 10
The process as a catalyst temperature detecting means for calculating the temperature of the catalyst installed in the catalytic converter (not shown) provided in the exhaust passage of the above is executed based on the detection result of S210.
The catalyst temperature T is calculated based on the following equation.

Catalyst temperature T = exhaust temperature + vehicle speed correction term + air-fuel ratio correction term × gas flow rate correction term Here, each value of the vehicle speed correction term, the air-fuel ratio correction term, and the gas flow rate correction term is detected in S210. It is set based on the vehicle speed, the air-fuel ratio, the intake air amount, and the data map shown in FIG. 6 stored in advance in the ROM 18b.

That is, as shown in FIG. 6 (A), the data map for setting the vehicle speed correction term has the vehicle speed as a parameter. The higher the vehicle speed, the smaller the vehicle speed correction term and the catalyst temperature T. It is calculated to be small. This is because the effect of cooling the catalyst by the outside air is promoted as the vehicle speed increases.

On the other hand, as shown in FIG. 6B, the data map for setting the air-fuel ratio correction term has the air-fuel ratio as a parameter, and the more the air-fuel ratio deviates from the theoretical air-fuel ratio, the more the air-fuel ratio correction term becomes. As the temperature decreases, the catalyst temperature T is calculated to be small. This is because when the air-fuel ratio deviates from the stoichiometric air-fuel ratio, the combustion efficiency in the engine 10 decreases, and in addition, the reduction reaction of the catalyst decreases and the reaction heat generated from the catalyst itself decreases.

As shown in FIG. 6C, the data map for setting the positive term of the gas flow rate has the gas flow rate, that is, the intake air amount as a parameter, and the gas flow rate increases as the intake air amount increases. The correction term becomes large and the catalyst temperature T is calculated to be large. This is because the output of the engine 10 increases and the thermal energy discharged from the exhaust passage increases as the intake air amount increases.

In this way, when the catalyst temperature T is calculated in S220, the difference (T-target temperature) between the calculated catalyst temperature T and the predetermined target temperature is the predetermined value (+ A) in the subsequent S230.
It is larger than the (degree). When it is determined that the difference (T-target temperature) is not larger than the predetermined value (+ A degree), the process proceeds to S240. And S240
Then, it is determined whether the difference between the catalyst temperature T and the predetermined target temperature (T-target temperature) is smaller than a predetermined value (-A degree),
When it is determined that the difference (T-target temperature) is not smaller than the predetermined value (-A degree), the process proceeds to S250.

Then, in S250, the shift schedule used in S120 of the shift control process described above is set as the normal shift schedule, and the shift schedule setting process is terminated. On the other hand, in S230, the difference between the catalyst temperature T and the predetermined target temperature (T-target temperature) is a predetermined value (+ A degree).
If it is determined that the shift schedule is larger than the shift schedule, the process proceeds to S260, the shift schedule used in S120 of the shift control process is set as the shift schedule for cooling, and a process as shift schedule changing means is executed to execute the shift schedule The setting process ends.

If it is determined in S240 that the difference between the catalyst temperature T and the predetermined target temperature (T-target temperature) is smaller than the predetermined value (-A degree), the process proceeds to S270.
A process as a shift schedule changing unit that sets the shift schedule used in S120 of the shift control process to the warm-up shift schedule is executed, and the present shift schedule setting process ends.

In other words, in the present shift schedule setting process, if negative determinations are made in S230 and S240, it is determined that the catalyst temperature T is within the range of ± A degrees from the target temperature, and the shift control is performed. The shift schedule used for is set to the normal shift schedule.
When an affirmative determination is made in S230, it is determined that the catalyst temperature T is higher than the target temperature by A degrees or more, the shift schedule used for shift control is set to the cooling shift schedule, and a positive determination is made in S240. In case of
Is determined to be lower than the target temperature by A degrees or more, and the shift schedule used for shift control is set to the warm-up shift schedule.

As described above, when the cooling shift schedule is set, the rotational speed of the engine 10 can be kept low even if the operating state is the same.
The exhaust energy discharged from the exhaust passage is reduced, and the temperature of the catalyst can be lowered. Conversely, when the warm-up shift schedule is set, the engine 10 speed increases even in the same operating condition, so exhaust energy increases and the catalyst temperature can be increased.

Therefore, according to the automatic transmission control system of the present embodiment, the catalyst temperature T can be brought close to the predetermined target temperature, and therefore, the target temperature can be regarded as a good exhaust gas purification rate of the catalyst. By setting in advance a value such that the exhaust gas purification rate by the catalytic converter can be maintained at a high level. Then, according to the automatic transmission control device of the present embodiment, such temperature control does not deteriorate the emission of the engine 10,
Moreover, it can be realized at low cost.

Here, in the above-described automatic transmission control device of the first embodiment, when the catalyst temperature T is lower than the target temperature by a predetermined value or more, the automatic transmission 12 is changed to the warm-up shift schedule. The shift timing and the lockup timing are delayed, but when the catalyst temperature T is low, use of the highest speed gear (fourth speed gear in the first embodiment) and lockup may be prohibited. Good.

Therefore, as a second embodiment, instead of using the warm-up speed change schedule, an automatic transmission control device for prohibiting the use and lockup of the high speed gear (fourth speed gear) will be described. . First, the automatic transmission control device of the second embodiment is compared with the device of the first embodiment,
The ROM 18b stores only two types of shift schedules for normal use and cooling, and in S270 of the shift schedule setting process shown in FIG. 5, the normal shift schedule is set and lockup is prohibited. The lock-up prohibition flag FLU and the fourth-speed gear prohibition flag FHG indicating prohibition of use of the fourth-speed gear are set to "1", respectively, and the lock-up prohibition flag FLU and the fourth-speed gear prohibition flag FHG are respectively set in S250. "0"
Is different from the point that the shift control process is executed as shown in FIG.

Therefore, the shift control process will be described below with reference to FIG. As shown in FIG. 7, in the shift control process of the second embodiment, the processes of S310 and S320 are added between S135 and S150 with respect to the shift control process of the first embodiment shown in FIG. Along with S140 and S16
The processing of S330 is added between 0 and 0.

That is, in the shift control process in the second embodiment, it is determined in S130 that the gear state detected in S110 is not the same as the control gear state calculated in S120, and the lockup is released in S135. Then S
Move to 310. Then, in S310, it is determined whether or not the control gear state indicates the fourth speed gear. When it is determined that the control gear state indicates the fourth speed gear, the process proceeds to S320, and the fourth speed gear inhibition flag FHG is set. It is determined whether "1" is set. Then, the fourth speed gear prohibition flag F
When it is determined that “1” is set in HG,
The shift control process is finished as it is.

If it is determined in S310 that the control gear state does not indicate the fourth speed gear, or if it is determined in S320 that the fourth speed gear inhibition flag FHG is not set to "1". As in the case of the first embodiment, the control signal is output to the gear stage control device 14 so as to switch the gear stage of the automatic transmission 12 to the gear stage indicated by the control gear state.

In the shift control process of the second embodiment, if it is determined in S140 that the lockup state detected in S110 is not the same as the control lockup state calculated in S120, the process proceeds to S330. Transition. Then, in S330, it is determined whether or not the lockup prohibition flag FLU is set to "1" and the lockup is released, and the lockup prohibition flag FLU is set to "1". When it is determined that is set and the lockup is released, the shift control process is ended as it is.

If a negative determination is made in S330, that is, if the lockup prohibition flag FLU is not set to "1" or it is determined that the lockup is performed, the first embodiment is performed. As in the case of the example, the process proceeds to S160, and a control signal is output to the gear stage control device 14 so as to switch the lockup state of the automatic transmission 12 to the state indicated by the control lockup state.

That is, in the second embodiment, when the catalyst temperature T is lower than the target temperature by a predetermined value or more and it is desired to raise the catalyst temperature T, 4 in the normal shift schedule is used.
The change point to the high-speed gear and the lock-up point at each gear are disregarded, so that the shift schedule is substantially changed. According to the automatic transmission control device of the second embodiment, the amount of data stored in the ROM 18b can be further reduced.

In the second embodiment described above, the highest speed 4
Although the change to the high speed gear and the lock-up in all the gears are prohibited, the number of gears for which use is prohibited and the number of gears for which lock-up is prohibited can be appropriately set. Here, in the above-mentioned first and second embodiments, a plurality of shift schedules are stored in advance in the ROM 18b, and one shift schedule is set according to the catalyst temperature T from among them. However, only the normal shift schedule may be stored in the ROM 18b and the shift schedule may be corrected according to the catalyst temperature T.

Further, instead of changing the shift schedule itself as in the first and second embodiments described above, the operating state of the vehicle applied to the shift schedule to calculate the control gear state and the control lockup state. The vehicle speed and the throttle opening may be corrected according to the catalyst temperature T.

Therefore, hereinafter, as a third embodiment, by having only a normal shift schedule and correcting the vehicle speed and the throttle opening applied to the shift schedule,
An automatic transmission control device that substantially changes the shift timing and lockup timing of the automatic transmission 12 will be described.

First, in the automatic transmission control system of the third embodiment, as compared with the system of the first embodiment, since only the normal shift schedule is stored in the ROM 18b, the shift as shown in FIG. That the schedule setting process is not executed, and that the shift control process is executed as shown in FIG.
Are different.

Therefore, the shift control process executed by the automatic transmission control device of the third embodiment will be described with reference to FIG. As shown in FIG. 8, when the execution of the shift control process is started, first, at S410, the exhaust temperature, the air-fuel ratio, the intake air amount, the vehicle speed, and the throttle opening are respectively set.
A process as an operating state detecting unit for detecting based on detection signals from the exhaust temperature sensor 28, the air-fuel ratio sensor 30, the intake air amount sensor 26, the vehicle speed sensor 22, and the throttle sensor 20 is executed. Then, in subsequent S420, the first
S of the shift schedule setting process (FIG. 5) in the embodiment
Just like 220, the processing as the catalyst temperature detecting means for calculating the catalyst temperature T based on the above-described arithmetic expression is executed.

Then, in subsequent S430, processing as an operating condition correcting means for correcting the current vehicle speed and the throttle opening detected in S410 is executed based on the calculated catalyst temperature T. Here, in the correction of the vehicle speed and the throttle opening, the difference between the target temperature and the catalyst temperature T (target temperature-catalyst temperature T) is obtained, and the lockup point is calculated from the value and the data map shown in FIG. After calculating the correction amount of the vehicle speed and the correction amount of the throttle opening used to calculate the gear shift point, the vehicle speed and the throttle opening detected in S410 are calculated as follows.
The procedure is such that the calculated correction amount is corrected respectively.

The data map for calculating the correction amount is stored in advance in the ROM 18b, and when the catalyst temperature T is lower than a predetermined temperature, lockup is difficult to be performed and the speed is lower. Is used, and when the catalyst temperature T is higher than a predetermined temperature, lockup is easily performed, and a higher gear is used. That is, as shown in FIG. 9, when the difference between the target temperature and the catalyst temperature T (target temperature-catalyst temperature T) becomes larger than a predetermined value, in other words, when the catalyst temperature T becomes lower than the predetermined temperature, the lock occurs. The correction amount of the vehicle speed for calculating the up point increases to the negative side, and the correction amount of the throttle opening for calculating the shift point of the gear position increases to the positive side. On the contrary, when the difference between the target temperature and the catalyst temperature T (target temperature-catalyst temperature T) becomes smaller than the predetermined value, in other words, when the catalyst temperature T becomes higher than the predetermined temperature, the lockup point is calculated. As the correction amount of the vehicle speed for increasing to the positive side,
The correction amount of the throttle opening for calculating the gear shift point of the gear stage is set to increase to the negative side.

After the vehicle speed and the throttle opening are corrected in this way, the ROM 18b is set in the subsequent S440.
The control gear state and the control lockup state are calculated based on the normal shift schedule stored in. here,
When calculating the control gear state, the actual vehicle speed detected in S410 and the throttle opening corrected in S430 are applied to the normal shift schedule, and when calculating the control lockup state, they are corrected in S430. The vehicle speed and the actual throttle opening detected in S410 are applied to the normal shift schedule. Accordingly, when the catalyst temperature T is low, the control lockup state is calculated based on the vehicle speed smaller than the actual vehicle speed, and the control gear state is calculated based on the throttle opening larger than the actual throttle opening. Will be calculated. On the contrary, when the catalyst temperature T is high, the control lockup state is calculated based on the vehicle speed higher than the actual vehicle speed, and the control gear state is calculated based on the throttle opening smaller than the actual throttle opening. Will be done.

After the control gear state and the control lockup state are calculated in this way, the gear state and the lockup state of the automatic transmission 12 are determined from the current control state for the gear stage control device 14 in S450. By the detection and subsequent processing of S460 to S490, a control signal is output to the gear stage control device 14 just as in S130 to S160 of the shift control processing in the first embodiment.

That is, in S460, it is determined whether or not the gear state detected in S450 is the same as the control gear state calculated in S440. If it is determined that it is the same, it is necessary to change the gear stage. If not, the process proceeds to S470. Then, in S470, it is determined whether or not the lockup state detected in S450 is the same as the control lockup state calculated in S440. If it is determined that the lockup state is the same as the control lockup state, the present shift control process is directly executed. finish.

If it is determined in S470 that the lockup state detected in S450 is not the same as the control lockup state calculated in S440, S490
Then, the process as the shift control means for outputting a control signal to the gear stage control device 14 so as to switch the lock-up state of the automatic transmission 12 to the state indicated by the control lock-up state is executed. This shift control process ends.

On the other hand, if it is determined at S460 that the gear state detected at S450 is not the same as the control gear state calculated at S440, then the flow shifts to S465 to release the lockup, and then to S480. Then, a process as a gear shift control means for outputting a control signal to the gear stage control device 14 so as to switch the gear stage of the automatic transmission 12 to the gear stage indicated by the control gear state is performed, and thereafter, this gear shift control process To finish.

When the control signal is output in the processing of S480 or S490, the gear stage control device 14 changes the shift state of the automatic transmission 12 based on the control signal. As described above, in the automatic transmission control device of the third embodiment, when the catalyst temperature T is lower than the predetermined temperature, the control lockup state is calculated based on the vehicle speed lower than the actual vehicle speed. The control gear state is calculated based on the throttle opening that is larger than the actual throttle opening.

As shown in FIG. 3, in the shift schedule of this embodiment, the lower the vehicle speed is, the lockup is not performed in each gear, and the larger the throttle opening is, the higher the vehicle speed is. It will not be changed to the high speed side gear. Therefore, when the catalyst temperature T is lower than the predetermined temperature, lockup becomes difficult to be performed, and the gear on the lower speed side is used, so that the engine 10
The number of revolutions becomes high and the temperature of the catalyst can be raised.

On the other hand, when the catalyst temperature T is higher than the predetermined temperature, the control lockup state is calculated on the basis of the vehicle speed higher than the actual vehicle speed, and also on the basis of the throttle opening smaller than the actual throttle opening. The control gear state is calculated. Then, as shown in FIG. 3, in the shift schedule of the present embodiment, the higher the vehicle speed, the easier the lock-up at each gear position is, and the smaller the throttle opening, the faster the vehicle speed becomes. It is designed to be changed to the gear on the side.

Therefore, when the catalyst temperature T is higher than the predetermined temperature, lockup is likely to be performed, and a higher gear is used to lower the engine speed and lower the catalyst temperature. You can That is, the third
In the automatic transmission control device of the embodiment, the parameters (vehicle speed and throttle opening) for calculating the control gear state and the control lockup state from the shift schedule are corrected by changing the shift schedule itself. Even in the same operating state, when the catalyst temperature T is lower than the predetermined temperature, the shift state of the automatic transmission 12 is controlled so that the rotation speed of the engine 10 becomes high, and conversely, the catalyst temperature T Is higher than the predetermined temperature, the shift state of the automatic transmission 12 is controlled so that the engine speed becomes low.

Therefore, the automatic transmission control device of the third embodiment also makes it possible to bring the catalyst temperature T close to the predetermined target temperature, so that the emission of the engine 10 is not deteriorated and the cost is low. Thus, the purification rate of exhaust gas by the catalytic converter can be maintained at a high level. In the third embodiment described above, when the control gear state is calculated in S440, the corrected value of only the throttle opening is used. However, the corrected value is also used for the vehicle speed. May be calculated. Then, in this case, the influence of the correction amount according to the catalyst temperature T can be largely reflected in the shift control.

Here, in the automatic transmission control device of each of the above-described embodiments, the catalyst temperature T is estimated from the exhaust temperature, the vehicle speed, the air-fuel ratio, and the intake air amount, so that the catalyst converter of the engine 10 is used. The automatic transmission 12 can detect the catalyst temperature T without additionally providing a temperature sensor or the like.
Shift control can be performed.

It should be noted that the catalyst temperature T is not determined by using the exhaust temperature, but based on various operating conditions such as vehicle speed, air-fuel ratio, intake air amount, etc.
May be estimated. Of course, the catalyst temperature T may be directly measured by a temperature sensor or the like.

[Brief description of drawings]

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

FIG. 2 is a schematic configuration diagram showing a configuration of an automatic transmission control device according to a first embodiment.

FIG. 3 is a graph showing a shift schedule used in the first embodiment.

FIG. 4 is a flowchart showing a shift control process in the first embodiment.

FIG. 5 is a flowchart showing a shift schedule setting process in the first embodiment.

FIG. 6 is an explanatory diagram illustrating a data map used for calculating a catalyst temperature in a shift schedule setting process.

FIG. 7 is a flowchart showing a shift control process in the second embodiment.

FIG. 8 is a flowchart showing a shift control process in the third embodiment.

FIG. 9 is an explanatory diagram illustrating a data map for correcting a vehicle speed and a throttle opening in the shift control process of the third embodiment.

[Explanation of symbols]

10 ... Engine 12 ... Automatic transmission 1
4 ... Gear stage control device 18 ... Electronic control device (ECU) 18a ... CPU 1
8b ... ROM 18c ... RAM 20 ... Throttle sensor 2
2 ... Vehicle speed sensor 26 ... Intake air amount sensor 28 ... Exhaust temperature sensor 3
0 ... Air-fuel ratio sensor

Claims (3)

[Claims] 1. A driving state detection means for detecting a driving state of a vehicle equipped with an internal combustion engine and an automatic transmission, and a shift schedule for determining the shift state of the automatic transmission in correspondence with the driving state of the vehicle. Storage means stored in advance, and shift control means for controlling the shift state of the automatic transmission based on the shift schedule stored in the storage means and the operating state of the vehicle detected by the operating state detecting means, In the automatic transmission control device provided with, the catalyst temperature detecting means for detecting the temperature of the catalyst installed in the catalytic converter provided in the exhaust passage of the internal combustion engine, and the temperature of the catalyst detected by the catalyst temperature detecting means are If it is lower than the predetermined target value, the shift schedule used by the shift control means is changed to a shift schedule in which the rotation speed of the internal combustion engine becomes high. However, when the detected temperature of the catalyst is higher than a predetermined target value, a shift schedule changing unit that changes the shift schedule used by the shift control unit to a shift schedule in which the rotation speed of the internal combustion engine becomes low. And an automatic transmission control device comprising: 2. A driving state detection means for detecting a driving state of a vehicle equipped with an internal combustion engine and an automatic transmission, and a shift schedule for determining the shift state of the automatic transmission in correspondence with the driving state of the vehicle. Storage means stored in advance, and shift control means for controlling the shift state of the automatic transmission based on the shift schedule stored in the storage means and the operating state of the vehicle detected by the operating state detecting means, In the automatic transmission control device provided with, the catalyst temperature detecting means for detecting the temperature of the catalyst installed in the catalytic converter provided in the exhaust passage of the internal combustion engine, and the temperature of the catalyst detected by the catalyst temperature detecting means are When it is lower than a predetermined target value, the operating state of the vehicle detected by the operating state detecting means and used by the shift control means is set to the rotational speed of the internal combustion engine. If the detected temperature of the catalyst is higher than a predetermined target value, it is detected by the operating state detecting means and is output by the speed changing control means. An automatic transmission control device comprising: an operating condition correcting means for correcting an operating condition of a vehicle to be used so that the rotational speed of the internal combustion engine becomes low and outputting the corrected operating condition to the shift controlling device. 3. The automatic transmission control device according to claim 1 or 2, wherein the catalyst temperature detection means estimates the temperature of the catalyst based on an operating state of a vehicle to determine the temperature of the catalyst. An automatic transmission control device characterized by detecting.