JPH02291434A - Integral control device for automatic transmission and engine - Google Patents

Abstract

PURPOSE:To obtain always the best transmission characteristics suitable for driving conditions by selecting and determining an optimal means from among a plural number of means which change the torque of an engine, depending on operating conditions of the engine and the state of transmission of an automatic transmission. CONSTITUTION:While an automatic transmission A is in the process of transmission, control is made to maintain good transmission characteristics by changing the torque of an engine B by a specified amount. In the said control device, operating conditions of the engine B are detected by a means C, and the type of transmission is detected by a means D. On the other hand, the torque of the engine B is changed with more than two kinds of means F. Depending on the detected operating conditions of the engine B and the type of transmission, the more than two kinds of means F which change the torque of the engine B are selected and determined by a means E. The torque of the engine B is thus changed with the optimal means F suitable for various driving conditions to obtain the best transmission characteristics.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an integrated control device for an automatic transmission and an engine, and in particular, an automatic transmission that maintains good transmission characteristics by changing engine torque by a predetermined amount during gear shifting. It relates to an integrated control device for aircraft and engines.

[Conventional technology]

The gear transmission mechanism includes a gear transmission mechanism and a plurality of frictional engagement devices, and the engagement of the frictional engagement devices is selectively switched by operating a hydraulic control device to achieve one of the plurality of gears. Automatic transmissions for vehicles configured to do this are already widely known. Such automatic transmissions for vehicles generally include a shift lever operated by the driver, a vehicle speed sensor that detects the vehicle speed, and a throttle sensor that detects the throttle opening, which is considered to reflect the engine load. The engagement state of the frictional engagement device can be automatically switched in accordance with the range of the shift lever and at least in relation to the vehicle speed and throttle opening. By the way, in the automatic transmission for a vehicle as described above, the engine torque is changed during gear shifting to obtain good shifting characteristics, and the durability of the Mm engagement device is ensured and improved. Various integrated controls have been proposed (for example, Japanese Patent Laid-Open No. 77138/1983). That is, this integrated control changes the amount of torque transmitted from the engine during gear shifting, and controls the amount of energy absorbed by each member of the automatic transmission or the frictional engagement device that restricts them, and This is an attempt to complete the shift with a small shift shock, give the driver a good shift feeling, and improve the durability of each frictional engagement device. As described above, shift control that controls engine torque during gear shifting is attracting attention as a way of controlling automatic gear shifting and the engine in an integrated manner, and is achieving considerable results. However, as means for changing the engine torque, there are several possible ways to change the engine torque, such as changing the ignition timing (retard) and changing the fuel supply concavity, and these are considered effective torque changing means in reality. However, regardless of whether the ignition timing is changed or the fuel supply amount is changed, there is a problem in that it is impossible to change the engine torque without limit due to other restrictions imposed by the engine. That is, when changing the ignition timing, realistically the retardation range from the set ignition timing BTD-C is, for example, 5° to 47°.
It is limited as follows. This is because if the ignition timing is retarded beyond this in order to reduce engine torque, the ignition timing may be too far off, resulting in a misfire, and the state of the emissions (exhaust gas) may deteriorate rapidly. Also, when changing the fuel supply amount, in order to avoid engine stoppage during gear shifting, it is important not to set the fuel supply amount extremely far from the standard fuel supply amount (injection time), such as completely shutting off the fuel. Can not. Also, during engine torque change control, the value of the air-fuel ratio A/F will deviate greatly from the stoichiometric air-fuel ratio, so in high-frequency shifting, it is not appropriate to change the fuel supply amount too much due to emissions concerns. It cannot be called a method. In view of these problems, in Japanese Patent Application Laid-Open No. 61-125930, when changing the engine torque, it is necessary to simply
This patent discloses a technique in which the torque is changed not only by using different types of changing means, but also by appropriately combining two or more types of torque changing means.

[Problem to be solved by the invention] However, in addition to the question of whether or not it is possible to simply reduce the torque by the necessary amount, specific means for changing the engine torque also require responsiveness, precision of control (accuracy of the amount of reduction), and usability conditions. There are advantages and disadvantages in terms of versatility, etc. Therefore, in addition to the question of whether or not it is possible to simply reduce the torque by the necessary amount, the most suitable type of torque change means does not necessarily depend on the driving conditions at that time. The problem is that they are not always the same. The present invention has been made in view of such problems, and when changing the engine torque during gear shifting, the engine torque is changed using the most appropriate torque changing means according to the various driving conditions at that time. It is an object of the present invention to provide an integrated automatic transmission and engine system which can obtain the best transmission characteristics as a result. [Means to solve the problem]

As summarized in FIG. 1, the present invention provides an integrated control device for an automatic transmission and an engine that maintains good gear shifting characteristics by changing engine torque by a predetermined amount during gear shifting. means for detecting the operating state of the engine; means for detecting the speed change time; two or more types of engine torque changing means for changing the engine torque; The above object has been achieved by including means for determining the type of the engine torque changing means to be used when changing the engine torque.

[Operation] In the present invention, first, when changing the engine torque during gear shifting, even if the required torque change amount is relatively small, the torque change may be made by, for example, ignition retardation or by reducing fuel injection tAI. In the case of torque change, even if the torque change itself is possible, it is determined (selected) which torque change means should be used to change the engine torque, depending on the driving conditions at that time. Therefore, it is possible to change the engine torque most appropriate to the current driving conditions, taking into account responsiveness, the degree of influence on the rise in exhaust gas temperature, the degree of deterioration of exhaust gas components, the possibility of misfire, etc. It becomes like this. The present invention further provides that, in determining the type of engine torque changing means, at least the engine operating state and the type of speed change should be considered in combination. This is because these conditions are considered to have the greatest influence among various driving conditions when selecting the type of torque changing means. Note that the "engine operating state" specifically includes parameters such as engine throttle opening, intake pipe negative pressure, engine rotation speed, engine cooling water temperature, and engine exhaust temperature. In addition, the "type of shift" specifically includes upshifting or downshifting, automatic shifting, manual shifting,
In the case of automatic transmission, from which gear to which gear should the gear be shifted?
Or, for example, what pattern the pattern select switch is set to when shifting, or in the case of manual shifting, from what range to what range (for example, from neutral range to drive range). It includes the concept of Also, by considering both the "engine operating state" and "shift type" in combination, for example, upshifting (downshifting) when the accelerator is depressed or when the accelerator is released. It is also possible to consider conditions such as upshifting or downshifting. In addition, specific methods for changing engine torque include retarding the ignition timing (!!angular control》fuel injection).
Possible methods include reducing the intake air m and reducing the intake air m.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 3 is an overall schematic diagram of an automatic transmission combined with an intake air amount sensing type automobile electronic fuel injection engine to which the present invention is applicable. Air taken in from the air cleaner 10 is sent to an air flow meter 12, a throttle valve 14, a surge tank 16, and an intake manifold 18 in order. This air is mixed with fuel injected from the injector 22 near the intake boat 20, and is further sent to the combustion chamber 26A of the engine body 26 via the intake valve 24. combustion'f
Exhaust gas generated as a result of combustion of the air-fuel mixture in f26A is discharged to the atmosphere via the exhaust valve 28, exhaust port 30, exhaust manifold 32, and exhaust pipe 34. The air flow meter 12 is provided with an intake air flow sensor 100 for detecting intake vortices. The throttle valve 14 rotates in conjunction with an accelerator pedal (not shown) provided at the driver's seat. This throttle valve 14 is provided with a throttle sensor 102 for detecting its degree. Further, a water temperature sensor 104 for detecting the engine cooling water temperature is disposed in the cylinder block 26B of the engine body 26, and a water temperature sensor 104 for detecting the oxygen concentration in the collecting part of the exhaust manifold 32 is disposed in the collecting part of the exhaust manifold 32. 02 sensor 106 is provided. Further, the distributor 38 having a shaft rotated by the crankshaft of the engine body 26 is provided with a crank angle sensor 108 for detecting a crank angle from the rotation of the shaft. The automatic transmission A/T also includes a vehicle speed sensor 100 for detecting the vehicle speed from the rotational speed of its output shaft, and a shift position sensor 1 for detecting the shift position.
12 are provided. Each of these sensors 1o0, 102, 104, 106, 1
The outputs of 08 and 1101112 are input to an engine computer (hereinafter referred to as ECU) 40. ECU40
Then, the fuel injection amount is calculated using input signals from each sensor as parameters, and the injector 22 is controlled to inject fuel for a predetermined time period corresponding to the fuel injection history. Note that an idle rotation control valve (ISCV) is provided in the circuit that communicates the upstream side of the throttle valve 14 and the surge tank 16.
) 42, and the idle speed is controlled by a signal from the ECU 40. The automatic transmission A/T also includes a pattern select switch 120 for selecting an E (economy) pattern for driving with an emphasis on fuel efficiency and a P (power) pattern for driving with an emphasis on power performance. is provided,
The signal is input to the ECT computer 50. In addition, signals from a brake lamp switch 122, a cruise control switch 124, an overdrive switch 126, etc. are also input to the ECT computer 50. As shown in detail in FIG. 4, the ECLJ40 includes a central processing unit (CPU) 4 consisting of a microprocessor.
0A, a memory 40B for storing control programs and various data, and an analogue controller having a multiplexer function for converting analog signals from the intake air wetness sensor ioo, water temperature sensor 104, etc. into digital signals and importing them. An input interface circuit for directly taking in outputs from the Goo digital converter (A/D converter) 40C, the throttle sensor 102, the 02 sensor 106, the crank angle sensor 108, the vehicle speed sensor 110, the shift position sensor 112, etc. 40D, and an ignition signal to the ignition coil 44, a fuel injection signal to the injector 22, and lscV4 according to the arithmetic processing results of the CPU 40A.
Idle rotation control signal to 2 and automatic gear change A/T
and an output interface circuit 40E for outputting signals to the ECT computer 50 for use. On the other hand, the ECT computer 50 includes a central processing unit (CPU) 50A consisting of a microprocessor, and a memory 50B for storing control programs, various data, etc.
, an input interface circuit 50D for inputting outputs from the throttle sensor 102, vehicle speed sensor 1101, shift position sensor 112, pattern select switch 1201, brake lamp switch 122, cruise control switch 124, and overdrive switch 126, and the CPU 50A. Solenoids S1 and S2 of the automatic transmission 1i1A/T
, and an output interface circuit 50E for outputting control signals to S3 and signals to ECU 40. The automatic transmission A/T is driven by a 2-3 shift valve 61 driven by the solenoid S1, a 1-2 shift valve 62 and a 3-4 shift valve 63 driven by the solenoid S2, and a 3-4 shift valve 63 driven by the solenoid S3. A lock-up clutch control valve 64 is provided, and shift valves 61 and 62 control a 3rd speed unit for obtaining a gear ratio configuration of 1st to 3rd speeds, and a shift valve 63 controls a 3rd speed unit for obtaining an overdrive gear ratio. The overdrive unit is controlled, and a lockup clutch that mechanically directly connects the input and output sides of the torque converter is controlled by a lockup clutch control valve 64. In addition, in this ECtJ40, the reciprocal of the time interval of the signal output from the crank angle sensor 108 every 30 degrees of crank angle is proportional to the engine rotation speed, and the output signal from the crank angle sensor 108 is Based on this calculation, the engine rotation speed is calculated. Further, the ECLJ 40 receives shift information (shift determination, shift command, lock-up clutch engagement permission, etc.) from the ECT computer 50, executes engine torque down control, and outputs this control information to the ECT computer 50. Based on this information, the ECT computer 50 issues a lock-up clutch release command and checks whether the above control is being performed reliably. In this embodiment, the ECLI 40 and the ECT computer 50 are separate units, and the ECLJ 40 determines and executes the amount and timing of engine torque reduction. It does not limit the area. The control flow executed in the ECU 40 will be shown below using FIG. In this control flow, 201A to 201G indicate steps for checking the value of the flag F for flow control. Since the initial value of this flag F is set to zero, the flow advances to step 202 after confirmation in step 201A. In step 202, it is determined whether or not there is a shift determination. If there is no specific shift determination, there is no need to change the engine torque during the shift according to the present invention, and the reset is performed as is. When it is determined in step 202 that a shift has been determined, the process proceeds to step 203, where an output (output for controlling the solenoids 81 to 83) for executing the shift is output. Next, in step 204, it is determined whether the shift in question was a power-on upshift (an upshift that can be performed with the accelerator depressed).If it was a power-on upshift, the process proceeds to step 207. It is determined whether or not the engine cooling water temperature T ('C) is equal to or higher than the set value of 60°C. If the set value is equal to or higher than 60°C, the process proceeds to step 208 and the state g (shift pattern) of the pattern select switch 120 is changed to the P pattern (power Pattern: It is determined whether the pattern is a pattern in which driving is performed with emphasis on power performance.P
If it is a pattern, the process proceeds to step 209, where the throttle opening degree θ is determined. For example, if it is determined that the throttle opening degree θ is 65% or more, the process proceeds to step 210, where it is determined whether or not the inertia phase has started. Here, the inertia phase refers to a period in which the engine rotational speed or the rotational speed of a rotating member in the automatic transmission actually changes due to the start of gear shifting. Until the inertia phase starts, the process proceeds to step 215, where the flag F is set to 2 and then reset. As a result of flag F being set to 2, step 20 is performed in the next flow.
The process proceeds to step 210 via 1A and 201G. If it is determined in step 210 that the inertia phase has started, the process proceeds to step 211, where an engine fuel cut command (fuel reduction command) is issued. This fuel cut command continues until it is determined in step 212 that the inertia phase has ended, and at the time it is determined that the inertia phase has ended, the process advances to step 213 and a fuel return command is issued. Then step 21
After flag F is set to zero in step 4, it is reset. On the other hand, in step 207, the engine cooling water temperature is
If it is determined that the torque is less than 1, the engine torque is changed by cutting the fuel regardless of the shift pattern or throttle opening. If it is determined in step 208 that the pattern is not P, the process proceeds to step 217 and the throttle opening θ is set to 85%.
It is determined whether or not it is 85% or more, and if it is 85% or more, the process proceeds to step 210 and subsequent steps to change the engine torque by cutting the fuel. If it is determined in step 209 that the throttle opening degree θ is less than 65%, the process proceeds to step 218, where the torque is changed by retard control in the same manner as in steps 210 to 214. When it is determined in step 204 that the shift is not a power-on upshift, the process proceeds to step 205, where it is determined whether the shift in question is a power-on downshift. If it was a power-on downshift, step 2
24 and 227, when the inertia phase has ended (or near the end), the process proceeds to step 225, and the retardation command is issued.
A command to reduce engine torque is issued. Thereafter, steps 226 and 228 wait until a predetermined period of time has elapsed, and when the predetermined period of time has elapsed, the process proceeds to step 221 and a retard return command is issued. As is clear from the explanation so far, in the case of a power-on upshift, the start of the inertia phase is detected, the engine torque change is started, and the torque is restored at the end of the inertia phase. In a downshift, torque is first reduced near the end of the inertia phase, and then torque is restored after a certain period of time. This is because changing the torque at such timing has the greatest effect, such as reducing shift shock caused by changing the torque. If it is determined in step 205 that it is not a power-on downshift, the process proceeds to step 206 and the gear shift is N.
It is determined whether or not there was a shift from the range to the D range (manual shift using the shift lever). If it was an N-4D shift, the process proceeds to step 229 and the engine speed Ne is 2500 "pill" or higher. It is determined whether the engine rotation speed Ne is 2 5 0 O
If the rpm is higher than that, the process proceeds to step 230 where the torque is changed by fuel cut, and step 231
and 234, the engine speed Ne is 250
Fuel cut control continues until it is determined that the amount has become 0 ram or less. Engine speed Ne is 250
If it is determined that the rpm is below O rpm, step 232
A fuel return command is issued at step 233, and 7lag F is set to zero and then reset at step 233. On the other hand, after it is determined in step 206 that it is an N-D shift, in step 229 the engine rotation speed Ne is set to 25.
When it is determined that the rpm is less than 0 0 rpm, the flag F is set to 7 in step 235, and steps 201A and 201A are performed.
The determination at step 229 continues via steps 201B and 201E. Engine speed Ne is 250 O
This flow is repeated as long as the engine speed Ne continues to be less than 2500 rpm, but when the engine speed Ne becomes 2500 rpm or more, the process proceeds to step 230, from which engine torque change control by fuel cut is started. It has become. The purpose of the above control flow can be summarized as follows. As shown in FIG. 5, although engine torque change by fuel cut is inferior in responsiveness to engine torque change by retard control, it is possible to obtain a larger torque reduction amount. Therefore, when the engine coolant temperature is 60° C. or higher and a power-on upshift is performed, engine torque change by fuel cut is adopted in the region of high throttle opening (65% or more in P pattern, 85% or more in E pattern). This is because it was taken into consideration that the thermal load on the friction material of the frictional engagement device becomes extremely high in this region when viewed from the automatic transmission side. In other words, in this region, the amount of torque change is large, the torque input to the automatic transmission side is correspondingly lowered, and the gear shift is performed with a lower clutch oil pressure, thereby improving the shift shock and the durability of the friction material. There is a need to improve gender. Therefore, the fact that engine torque change by fuel cut can reduce the torque to a greater extent than engine torque change by retard control is utilized to the fullest extent. In this case, the reason why the threshold value for the throttle opening θ was made different depending on the position of the pattern select switch is that the P pattern has a higher shift point, so the thermal load on the friction material is correspondingly higher, resulting in a large engine torque drop. Because you need it. On the other hand, for power-on upshifts at low throttle speeds, the engine torque is changed by retarding the ignition angle with emphasis on controllability. This is because in the region of low throttle opening, the thermal load on the clutch is generally low, so a large amount of torque change is not required.
This is because it is desirable to employ torque change using ignition retardation, which has higher controllability, that is, better responsiveness, and can accurately realize the intended torque change amount. Also, when the engine torque is reduced during a power-on downshift, the engine torque is changed by retarding the ignition angle. This is because engine torque reduction in a power-on downshift generally needs to be performed in a short period of time immediately before the one-way clutch locks, so it is preferable to change the torque by responsive ignition retardation. It is difficult to ensure a large torque change m when changing torque by ignition retardation, but in the case of power-on downshift,
Since shifting is achieved by releasing the clutch, there is no problem in terms of durability even if the amount of torque change cannot be large. On the other hand, when the shift lever is moved from the neutral range to the drive range, engine torque is reduced by cutting fuel. This is because the use restriction conditions for engine torque reduction due to ignition retardation are relatively strict. For example, if you change the engine torque by retarding the ignition when the engine coolant IT is low, that is, when warming up has not yet been completed, there is a risk of a misfire. ``Limit control'' is often executed to cancel the change in engine torque due to the engine torque change or to reduce the retard angle m. However, the shift from the neutral range to the drive range is often performed immediately after the engine has been started, that is, when the engine has not warmed up at all. This is because it is preferable to change the engine torque through a fuel cut, which has relatively gentle usage restrictions, than to change the engine torque through a fuel cut. For the reason stated above, when the engine cooling water temperature is less than 60°C, engine torque is changed by cutting fuel. In other words, in the case of engine torque change control using ignition retardation,
When the cooling water temperature is low, there is a problem in that it is difficult to perform retard control because there is a risk of misfire. In this case, as a countermeasure, for example, a method of lowering the shift point to reduce the thermal load on the clutch may be considered, but this would inevitably lead to a decrease in drivability (power performance) and a feeling of discomfort with the degree of depression of the accelerator. In this embodiment, when the engine cooling water temperature is less than 60° C., a fuel cut method is used to change the engine torque, so that a sufficient change in the engine torque can be performed without causing such problems. Furthermore, the shift characteristics from the neutral range to the drive range can be favorably improved without being restricted by usage restriction conditions. Figure 6 summarizes the above. Note that the engine torque changing means is not limited to the above two means, and for example, a method of cutting the intake air may also be considered. Specifically, the intake air cut can be realized by closing the engine throttle valve independently of the accelerator pedal. Therefore, although the responsiveness is slightly inferior, there is an advantage that there is no adverse effect on the engine, exhaust gas, etc. The advantage of this is that, for example, if exhaust gas becomes too hot due to engine operating conditions, reducing engine torque by retarding the ignition timing will cause the exhaust temperature to rise further. It can be used by switching to

【Effect of the invention】

As explained above, according to the present invention, since the engine torque changing means is selected and determined depending on the engine operating state and the type of gear change, the characteristics of each engine torque changing means can be fully utilized. An excellent effect can be obtained in that the torque can be changed in any state.

[Brief Description of the Drawings] Fig. 1 is a block diagram showing the gist of the present invention, and Fig. 2 is a block diagram showing the gist of the present invention.
FIG. 3 is a flowchart showing a control flow executed in the embodiment device of the present invention, and FIG. 3 is an overall overview of an automatic transmission combined with an intake air carrier sensing type electronic fuel injection engine for a vehicle, according to the embodiment device described above. FIG. 4 is a block diagram extracting and showing the input/output relationship of the engine and the automatic transmission dawn,
Fig. 5 is a diagram summarizing the characteristics of engine torque changes due to ignition retardation and fuel cut, and Fig. 6 shows how the means for changing engine torque is changed depending on the engine operating state and the type of gear shift. FIG. 40...Engine computer (ECU), 50...
・ECT computer, 102... Throttle sensor, 104... Engine cooling water temperature sensor, 108... Crank angle sensor (engine speed sensor), 100... Vehicle speed sensor, 112... Shift position sensor, 120 ...Pattern select switch.

Claims (1)

[Claims] (1) In an integrated automatic transmission and engine control device that maintains good gear shifting characteristics by changing engine torque by a predetermined amount during gear shifting, means for detecting the operating state of the engine, and gear shifting. means for detecting the type of the engine; two or more types of engine torque changing means for changing the engine torque; and the engine used when changing the engine torque according to at least the engine operating state and the type of speed change. An integrated control device for an automatic transmission and an engine, comprising: means for determining the type of torque changing means;