JP5115846B2 - Engine control device - Google Patents

Description

  The present invention relates to an engine control device, and more particularly to engine control that includes a plurality of external accessories driven by the engine and a plurality of engine-related accessories, and controls the output of the engine provided with a stepped transmission. Relates to the device.

The torque of the vehicle engine is mainly controlled by a throttle valve linked to an accelerator pedal. In the engine control system, for the purpose of improving fuel efficiency, various auxiliary machines such as an exhaust gas recirculation system (EGR) and a variable valve timing mechanism (VVT) are installed in the low accelerator opening (low throttle opening) region. In the high accelerator opening (high throttle opening) region, the exhaust gas recirculation device is stopped and the variable valve timing mechanism is set to torque priority for the purpose of torque priority. At the same time, torque is increased by temporarily stopping compressors and alternators (generators) of air conditioners (air conditioners).
For this reason, even if the accelerator opening (throttle opening) increases slowly and smoothly, the engine torque drives / stops (ON / OFF) the exhaust gas recirculation device, variable valve timing mechanism, air conditioner compressor, alternator, etc. Depending on the setting change, it may increase or decrease stepwise.
In vehicles equipped with an automatic stepped transmission, the gear speed and lockup state of the stepped transmission are generally switched by the accelerator opening and the vehicle speed, and the engine torque gain is controlled. There is a problem that the torque changes stepwise with respect to the throttle opening.

For this reason, when operating a certain load, a conventional engine control device selects another load indicating a drive configuration that cancels the change in driving force when this load is activated, Some control is performed so as not to cause rotational fluctuations in engine output with other loads that cancel the driving force of the operating load.
Japanese Patent No. 2989327

Also, conventional engine control devices detect changes in the opening speed of the throttle valve based on the depression speed of the accelerator pedal that rotates the throttle valve, and temporarily turn on the engine cooling fan and air conditioner compressor during vehicle acceleration. There is something to stop.
Japanese Utility Model Publication No. 60-82542

Conventional engine control devices operate the air conditioner by synchronizing the timing of stopping the air conditioner when the vehicle is accelerating, and then returning the air conditioner to the operating state in synchronism with the torque reduction during shifting of the automatic transmission. Some reduce the shock when returning to the state.
JP-A-5-104943

Some conventional engine control devices include a generator driven by the engine, and stop the driving of the generator during the acceleration process of the engine to use the entire output of the engine for acceleration.
JP-A-55-71101

Some conventional engine control devices attempt to improve acceleration performance by stopping the EGR when the brake is released to enter an acceleration transition state.
JP 2005-90273 A

As described above, in a vehicle equipped with an engine with a stepped transmission, the driving wheel torque changes in a stepped manner with respect to the accelerator opening (throttle opening) due to the control of the engine and the stepped transmission. Or may vary depending on the situation and may deviate from the driver's intention. For this reason, the driver needs to correct the accelerator opening and manually select the gear stage. As a specific example, hunting for gear shifting on an uphill road is raised.
That is, if the accelerator pedal is artificially released while traveling on an uphill road, the gear stage may be automatically shifted up depending on the shift control. At that time, the drive torque may be excessively reduced due to a balance of conditions including gradient and artificial operation. In that case, the vehicle is stalled, and the accelerator pedal is artificially re-pressed correspondingly, so that the vehicle is automatically kicked down according to the shift control. Then, the driving torque increases excessively from the balance of each condition including the gradient and the artificial operation, and the accelerator is returned. In this way, hunting occurs due to deviation from the driver's intention. In order to prevent this hunting, there is a technique for performing control to temporarily hold a specific gear stage. However, if the control is uniformly applied even in a state where only a slight load change is required, there is a problem that fuel consumption may be impaired. There is.
In general, the engine control of the exhaust gas recirculation device, variable valve timing mechanism, air conditioner compressor, alternator, air-fuel ratio, etc., and the gear stage and lockup state of the automatic stepped transmission are controlled independently. Therefore, there is a problem that it cannot be said that the best setting in terms of fuel consumption and drivability is selected for the required drive wheel torque.
And most of each technique of the said literature becomes independent individual control. Canceling the load is not suitable for small vehicles with a small absolute number of auxiliary machines. Synchronizing with the speed change does not lead to an improvement in fuel consumption.

The present invention relates to integrated engine output control including control of throttle opening and external auxiliary equipment and engine-related auxiliary equipment in a transient state or a steady state during traveling of the vehicle. By optimizing control with respect to load control in the state and coordinating throttle control, the driving wheel torque required by the driver is always realized correctly, and as a comprehensive powertrain system, the entire torque range The main purpose is to achieve the best fuel efficiency.
At that time, while maintaining the output feeling of the engine to ensure the driving feeling, the improvement of fuel economy performance in the transient state and the reduction of exhaust gas are realized, and the balance is achieved. It aims to plan.
In addition, the present invention provides a change from a low load to a high load of the engine, that is, a change from a low throttle opening to a high throttle opening, or a change from a low acceleration request to a high acceleration request, particularly in a transient state. In the above, when the required torque changes slowly over time, the torque smoothly follows, and the optimized control is realized so as to eliminate or reduce the stepped or pulse-like change as much as possible. The purpose is to realize the same optimized control even when the load is changed from a high load to a low load.

According to the present invention, a stepped transmission is provided in an engine of a vehicle, and an external auxiliary machine driven by the engine reflects an artificial operation of an accelerator pedal or is independent of an artificial operation of the accelerator pedal. Engine control provided with an engine-related accessory that includes an operable electronic throttle valve and can change the output torque of the engine, and a control means for controlling the external accessory, the engine-related accessory, and a stepped transmission In the apparatus, the control means sets the order in advance for switching timing of the driving / stopping state of the external auxiliary machine, engine auxiliary auxiliary machine, and stepped transmission, and these external auxiliary machine, engine auxiliary auxiliary machine, The electronic throttle valve has a function of changing and controlling the throttle opening of the electronic throttle valve in accordance with any state change of the transmission. The throttle opening of the sub throttle valve is gradually increased, and when the predetermined throttle opening is reached, the switching of the driving / stopping state of the external auxiliary machine, the auxiliary engine associated with the engine, and the stepped transmission is changed according to the order of the switching timing. Control is performed sequentially, and the throttle opening is adjusted so that a torque change due to this change in switching does not occur .

According to the engine control device of the present invention, the driving wheel torque set according to the relationship with the vehicle speed is not changed stepwise in response to the artificial operation of the accelerator pedal (torque request based on the accelerator opening). The opening degree and the driving state of the auxiliary machinery can be set to an optimal state balanced with respect to fuel consumption, noise, and exhaust gas emission.
As a result, for example, the torque change when changing from low load to high load is moderated to obtain a smooth acceleration feeling, or conversely, the torque change when changing from high load to low load is moderated. Further, it is possible to improve fuel efficiency by preventing shift hunting, or by using a gear step that is one step higher than in the prior art, or by locking up in steady running.
In addition, the engine control apparatus of the present invention can increase the relative torque while keeping the throttle opening relatively small under the limited conditions, and can suppress an excessive accelerator operation.

The present invention relates to an engine control device that controls the output of an engine that includes a plurality of external accessories driven by the engine and a plurality of engine-accompanying accessories provided in the engine. Concerning integrated engine output control including control of opening and external auxiliary equipment and engine auxiliary equipment in a transient state, engine combustion control, external load control, and speed change from acceleration / deceleration to constant speed running It relates to integrated control of control. Here, even during the transient state, when the vehicle is slowly accelerating from the steady running state (when torque is increased or when power is turned on), the shift down of the automatic stepped transmission is performed during the latter period when the slow acceleration continues. The integrated control of engine combustion control, external load control, and shift control in a state until it is performed will be described.
Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention. 1 is a flowchart of the engine control device, FIG. 2 is a time chart of the engine control device, and FIG. 3 is a block diagram of the engine control device. In FIG. 3, 1 is an engine mounted on a vehicle, and 2 is a stepped transmission.
An engine 1 of a vehicle is provided with an electronic throttle valve 3 that can be operated in reflection of an artificial operation of an accelerator pedal or independently of an artificial operation of the accelerator pedal, an injector 4 that injects fuel, and an ignition plug An ignition coil 5 is provided to cause a spark.
The engine 1 is provided with an exhaust gas recirculation device (EGR) 6 and a variable valve timing mechanism (VVT) 7 as an engine accessory that can change the output torque of the engine. The exhaust gas recirculation device 6 includes an EGR valve 8 that controls the amount of exhaust gas recirculated to the intake system of the engine 1. The variable valve timing mechanism 7 includes a timing control valve 9 that controls the opening / closing timing of the intake valve and the exhaust valve. Further, the engine 1 is provided with a compressor 11 of an air conditioner (air conditioner) 10 and an alternator (generator) 12 as an external auxiliary machine driven by the engine 1.
The stepped transmission 2 includes a torque converter 13 that converts and transmits the output torque of the engine 1 and a gear transmission mechanism 14 that includes a plurality of gear stages that convert and output the torque transmitted by the torque converter 13. The lockup mechanism 15 is provided to connect the pump of the torque converter 13 and the turbine to eliminate slippage . The stepped transmission 2 switches (shifts) the gear stage of the gear transmission mechanism 14 by the transmission control means 16 and couples / releases the lockup mechanism 15 of the torque converter 13.

The engine 1 is controlled by the control means 18 of the control device 17. The control means 18 is connected to the electronic throttle valve 3, the injector 4, and the ignition coil 5, and the EGR valve 8 of the exhaust gas recirculation device 6, which is an engine accessory, and the timing control of the variable valve timing mechanism 7. A valve 9 is connected, and a compressor 11 of an air conditioner 10 that is an external accessory driven by the engine 1 and an alternator 12 are connected. The control means 18 is connected to the transmission control means 16 of the stepped transmission 2.
The control means 18 includes an air flow sensor 19 that detects the amount of air taken into the engine 1, an intake air temperature sensor 20 that detects the intake air temperature of the air taken into the engine 1, and the crank angle of the crankshaft of the engine 1. A crank angle sensor 21 to detect, a cam angle sensor 22 to detect the cam angle of the cam shaft of the engine 1, a battery current sensor 23 to detect the charge / discharge current of the battery of the engine 1, and evaporated fuel to the intake system of the engine 1 An evaporator temperature sensor 24 that detects the evaporator temperature that releases the vehicle, a vehicle speed sensor 25 that detects the speed of the vehicle, an accelerator opening sensor 26 that detects the accelerator opening (depression state) of the accelerator pedal, and a headlight state (lights on) Headlight switch 27 for inputting “off” and water temperature sensor for detecting the water temperature (cooling water temperature) of the engine 1 28, an atmospheric pressure sensor 29 for detecting the atmospheric pressure, and connects the air conditioner switch 30 to enter air conditioner air conditioning instructing (air conditioner operation state).
The control means 18 inputs signals from these sensor switches 19 to 30, outputs a target opening degree to the electronically controlled throttle valve 3 to control the throttle opening degree, and inputs information on the actual opening degree to the injector 4. An injection instruction is output to control the injection amount, and an ignition instruction is output to the ignition coil 5 to control the ignition timing. Further, the control means 18 inputs signals from these sensor switches 19 to 30, outputs an ON / OFF instruction to the compressor 11 which is an external auxiliary device, switches the driving / stopped state, and instructs the alternator 12 to turn on / off. Is output to switch the driving / stopping state, the target opening is output to the EGR valve 8 of the exhaust gas recirculation device 6 that is an auxiliary engine of the engine, the exhaust gas recirculation amount is controlled, and the timing control of the variable valve timing mechanism 7 The target gear advance amount is output to the valve 9 to control the valve timing, and the gear stage and the lockup instruction are output to the transmission control means 16 to output the gear stage and the lockup mechanism of the gear transmission mechanism 14 of the stepped transmission 2. 15 is controlled, and information such as a gear stage, a lock-up state, and a transmission oil temperature is input from the transmission control means 16.

In the control device 17 of the engine 1, the control means 18 includes a drive / stop state of the compressor 11 and the alternator 12 that are the external auxiliary devices, an exhaust gas recirculation device 6 that is the auxiliary device of the engine, and variable valve timing. An order is set for the switching timing between the driving / stopping state of the mechanism 7, the meshing state of the gear transmission mechanism 14 of the stepped transmission 2 and the coupling / release state of the lockup mechanism 15, and the external auxiliary machine and engine It has a function of changing and controlling the throttle opening of the electronic throttle valve 3 in accordance with any state change of the auxiliary accessory or stepped transmission.
During acceleration, the control means 18 gradually increases the throttle opening of the electronic throttle valve 3 toward a predetermined throttle opening, and when the predetermined throttle opening is reached, the external compensation is performed according to the order of switching timing set in advance. Control to sequentially change the driving / stopping state of the machine, the engine accessory, and the stepped transmission.
The control means 18 sets the order of switching timing in the order of external auxiliary equipment, engine-related auxiliary equipment, and stepped transmission.
The engine-related accessory includes an exhaust gas recirculation device 6 and a variable valve timing mechanism 7. The control means 18 controls the exhaust gas recirculation device 6 to change the driving / stopped state before the variable valve timing mechanism 7.

Next, the operation of this embodiment will be described.
The control device 17 of the engine 1 sets a target drive wheel torque map based on the accelerator opening / vehicle speed in the control means 18 so that the target drive wheel torque obtained from the accelerator opening / vehicle speed is obtained from the target drive wheel torque map. In addition, the throttle opening of the electronic throttle valve 3 of the engine 1, the exhaust gas recirculation device 6, the variable valve timing mechanism 7, the compressor 11 of the air conditioner 10, the alternator 12, and the step-variable transmission are provided so that the fuel consumption and the drivability are the best. Engine-related auxiliary equipment, external auxiliary equipment, stepped transmission 2 such as gear stage (meshing state) of gear transmission mechanism 14 of machine 2 and lockup state (coupled / released state) of lockup mechanism 15 The overall driving / stopping state is controlled.
Specifically, the control device 17 first sets the settings of all the devices such as the engine accessory, external accessory, and stepped transmission 2 as fuel efficiency priority (engine accessory accessories such as the exhaust gas recirculation device 6: fuel efficiency priority). Assuming control, gear stage of gear transmission mechanism 14 of stepped transmission 2: highest stage, lockup mechanism 15: ON, external auxiliary equipment such as compressor 11 of air conditioner 10: normal operation), and preset target From the driving wheel torque map, the target driving wheel torque is calculated when the throttle opening is fully open in the assumed state. This is because the fuel efficiency is generally best in the high throttle opening range.
When the driving wheel torque is lower than the target driving wheel torque in the initial state, the control device 17 determines whether the engine-related auxiliary device, the external auxiliary device, or the stepped transmission 2 is in accordance with the priority set in terms of fuel consumption and drivability. Any one of them is assumed to give priority to torque (stop of engine-related auxiliary equipment such as exhaust gas recirculation device 6, stop of external auxiliary equipment such as compressor 11 of air conditioner 10, and reduction of gear stage of stepped transmission 2 by one stage) Then, the maximum driving torque in that state is compared with the target driving wheel torque again. In this state, when the target drive wheel torque is still below, another one of the engine-accompanying auxiliary machine, the external auxiliary machine, and the stepped transmission 2 is changed to torque priority. The control device 17 repeats this process until the target drive wheel torque is exceeded. When the actual driving wheel torque exceeds the target driving wheel torque, the throttle opening is adjusted to coincide with the target driving wheel torque.

As shown in FIG. 1, the control device 17 of the engine 1 drives the electronic throttle valve 3, the exhaust gas recirculation device 6, the variable valve timing mechanism 7, the compressor 11, the alternator 12, the gear speed change mechanism 14, and the lockup mechanism 15. Control to set the stop state.
When the control is started (A01), the control device 16 calculates the target drive wheel torque from the accelerator opening and the vehicle speed (A02), assuming that the gear stage of the stepped transmission 2 is initially the highest stage, and the target drive wheel. The target turbine torque and the target turbine speed are calculated from the torque and the vehicle speed (A03), and it is determined whether the gear stage, the target turbine torque, and the target turbine speed are set so that the lockup mechanism 15 can be turned on (coupled: lockup) ( A04).
If this determination (A04) is YES, the lockup mechanism 15 is turned on (coupled: lockup) (A05), engine speed = target turbine speed (A06), target engine OUT torque = target turbine torque (A07). When this determination (A04) is NO, it is determined whether or not the lockup mechanism 14 can be turned ON (coupled: lockup) with a gear step lower by one step (A08).
When this determination (A08) is YES, the gear stage of the stepped transmission 2 is set to one paragraph (A09), and the process returns to the process (A03). If this determination (A08) is NO, the lockup mechanism 15 is turned off (released) (A10), the engine speed is calculated from the characteristics of the torque converter 13 (A11), and the target engine OUT is calculated from the characteristics of the torque converter 13. Torque is calculated (A12).
After obtaining the engine speed in (A06) and (A11), the engine speed of (A06) and (A11) in the setting of the equipment including the current engine-related auxiliary equipment, external auxiliary equipment, and stepped transmission 2 The maximum engine-generated torque with the accelerator fully open is calculated from the number (A13). The initial value is to give priority to fuel consumption for all devices.
In addition, after obtaining the engine speed in (A06) and (A11), the auxiliary machine torque is calculated in the assumed setting of the equipment including the current auxiliary engine, external auxiliary machine, and stepped transmission 2. (A14). Note that the initial value is that all devices are in normal operation.
Further, the target engine generated torque is calculated by adding the auxiliary machine torque obtained in (A14) to the target engine OUT torque obtained in (A07) and (A12) (A15).
Next, it is determined whether the maximum engine generated torque obtained in (A13) is equal to or greater than the target engine generated torque obtained in (A15) (A16).
If the maximum engine generated torque is equal to or greater than the target engine generated torque and the determination (A16) is YES, the state of the device such as the engine-related auxiliary device in that state, the setting of the device such as the engine-related auxiliary device, and the stepped transmission 2 The gear stage of the gear transmission mechanism 14 and the state of the lock-up mechanism 15 are determined, and the target throttle opening is calculated and determined from the settings of the target engine generated torque, the target engine speed, the engine accessory, and the like, The gear stage and lockup state of the stepped transmission 2 are determined (A17), and the control is ended (A18).
If the maximum engine generated torque is less than the target engine generated torque and the determination (A16) is NO, it is determined whether there is an operating auxiliary machine and it can be stopped (A19). If this determination (A19) is YES, one of the operating auxiliary machines is stopped (A20), the process returns to (A14), and the auxiliary machine torque is calculated again. When this determination (A19) is NO, it is determined whether there is a device such as an engine-related auxiliary device that can be changed from fuel efficiency priority to torque priority (A21).
If this determination (A21) is YES, one of the devices such as the engine accessory is changed to the torque priority setting (A22), the process returns to (A13), and the maximum engine generated torque is calculated again. If this determination (A21) is NO, it is determined whether the lockup mechanism 14 is ON (coupled: lockup) (A23).
When this determination (A23) is YES, the process proceeds to determination (A08) as to whether the lockup mechanism 15 can be turned on (coupled: lockup) with the gear position one step lower. When this determination (A23) is NO, the process proceeds to a process (A09) in which the gear stage of the stepped transmission 2 is set to one paragraph. Therefore, when the determination (A23) is NO, the gear stage is lowered by one stage or the lockup mechanism 14 is turned off (released), and the steps from the process (A03) to the process (A15) are executed again to generate torque. calculate. This process is repeated until the determination (A16) is satisfied (YES).

FIG. 2 shows the driving / stopping states of the external accessory, the engine-related accessory, and the stepped transmission 2 when the accelerator pedal is slowly depressed (accelerator opening is increased) at a constant vehicle speed.
Conventionally, as shown by a broken line in FIG. 2, when the accelerator pedal is slowly depressed at a constant vehicle speed, the accelerator opening increases and the throttle opening of the electronic throttle valve 3 opens. The increase rate of the air amount with respect to the accelerator opening decreases, and the drive wheel torque does not increase after the throttle opening reaches a certain value k or more and the air amount becomes maximum (t1).
Thereafter, when the accelerator pedal is further depressed, the exhaust gas recirculation device (EGR) 6 is turned off (stopped) at an appropriate accelerator opening (t3), and the variable valve timing mechanism (VVT) 7 is switched to the torque priority setting (t4). When the lockup mechanism 15 is turned off (released) (t5) and the accelerator pedal is further depressed, the gear stage of the gear transmission mechanism 14 is lowered by one stage (t7).
The driving wheel torque changes stepwise with respect to the accelerator opening (t3, t4, t5), and is insufficient before the gear stage is lowered by one stage (before t7), and after the gear stage is lowered by one stage (after t7). ) Is oversized. Further, the engine generated torque increases and changes stepwise with respect to the accelerator opening by the exhaust gas stop amount / variable valve timing torque setting (t3, t4), and after the gear stage is lowered by one step (after t7). Increased due to increased rotation.
Conventionally, since the driving wheel torque is small as shown by the broken line, in order to obtain the same torque as the solid line, it is necessary to quickly depress the accelerator pedal accordingly. In many cases, the auxiliary machine is controlled independently except in the vicinity of the accelerator fully open.

As shown by the solid line in FIG. 2, the control device 17 of the engine 1 of the present invention increases the accelerator opening and the throttle opening of the electronic throttle valve 3 when the accelerator pedal is slowly depressed at a constant vehicle speed. As the throttle opening increases, the rate of increase of the air amount with respect to the accelerator opening decreases, and when the throttle opening reaches a certain value k and the air amount becomes maximum and the driving wheel torque does not increase (t1), The alternator 12 is turned off (stopped), and the throttle opening is closed from a constant value k by an opening corresponding to the stopped alternator torque. The engine generated torque is reduced by the alternator torque by closing the throttle opening.
When the accelerator pedal is depressed from the time (t1), the throttle opening that is closed by the opening corresponding to the alternator torque is opened from the constant value k, and when the throttle opening reaches the constant value k and the air amount becomes maximum (t2). Then, the compressor 11 of the air conditioner 10 is turned off (stopped), and the throttle opening is closed from the constant value k by the opening corresponding to the stopped compressor torque. The engine generated torque is reduced by the compressor torque by closing the throttle opening.
When the accelerator pedal is depressed from time (t2), the throttle opening that is closed by the opening corresponding to the compressor torque is opened from the constant value k, and when the throttle opening reaches the constant value k and the air amount becomes maximum (t3). Then, the exhaust gas recirculation device 6 is turned off (stopped), and the throttle opening is closed from a constant value k by an opening corresponding to the increased torque due to the exhaust gas recirculation device 6 being stopped . The engine generated torque is offset by the reduced torque due to closing the throttle opening, and the increased torque due to the stop of the exhaust gas recirculation device 6 is not reduced.
When the accelerator pedal is depressed from time (t3), the throttle opening that is closed by the opening corresponding to the increased torque due to the exhaust gas stop is opened from the constant value k, and the throttle opening reaches the constant value k and the air amount becomes maximum. Then (t4), the variable valve timing mechanism 7 is switched from the fuel consumption setting to the torque setting, and the throttle opening is closed from the constant value k by the opening corresponding to the increased torque due to the switching to the torque setting. The increased torque generated by switching to the torque setting is offset by the decreased torque generated by closing the throttle opening, and does not decrease.
Depressing the accelerator pedal from time (t4) opens the throttle opening that is closed by the opening corresponding to the increased torque by switching from the constant value k to the torque setting, the throttle opening reaches the constant value k, and the air amount When the maximum is reached (t6), the gear stage of the gear transmission mechanism 14 is lowered by one stage (shift down), the alternator 12 is turned on (driven), the compressor 11 of the air conditioner 10 is turned on (driven), and the exhaust gas recirculation device 6 is turned on (driven), the variable valve timing mechanism 7 is switched from torque setting to fuel consumption setting, and the throttle opening is kept constant by the opening corresponding to the increased torque when the gear stage is lowered by one or the device such as the alternator 12 is turned on. Close from value k. The engine generated torque is reduced by the increased torque by closing the throttle opening.
When the accelerator pedal is further depressed from time point (t6), the throttle opening is closed by the opening corresponding to the increased torque due to the lowering of the gear stage from the constant value k and the turn-on of the equipment such as the alternator 12, etc. Torque increases.
The throttle opening (skip amount) when the driving of the auxiliary machine such as the alternator 12 is stopped and closed from a constant value k is an opening corresponding to the torque required for driving the auxiliary machine such as the stopped alternator 12. Yes, by setting this opening degree in advance, it is possible to feed-forward control the throttle opening reduction when the auxiliary machine is stopped.
The control device 17 of the engine 1 has the compressor 11 and the alternator 12 of the external auxiliary equipment and the exhaust gas recirculation device 6 of the auxiliary equipment of the engine and the above-mentioned priority order so as to match the target driving wheel torque set by the accelerator opening. The variable valve timing mechanism 7, the gear stage of the stepped transmission 2, and the throttle opening of the electronic throttle valve 3 are controlled. Thereby, the control device 17 of the engine 1 realizes driving wheel torque linear to the accelerator opening. Further, the control device 17 of the engine 1 is improved in noise and fuel consumption due to a decrease in the frequency of downshift of the stepped transmission 2, and fuel efficiency after downshift is also improved.

The control device 17 of the engine 1 optimizes the entire power unit including the engine 1 and the stepped transmission 2 by giving priority control to all elements that affect the output torque of the engine 1 and performing integrated control ( This will reduce fuel consumption and improve drivability. In particular, in multi-stage stepped transmissions, the difference in driving force for each gear stage is large, so the difference is optimized by compensating for the difference by controlling the drive / stop state of other engine-related auxiliary equipment and external auxiliary equipment. There are benefits. For example, if the stepped transmission is conventionally required to be downshifted, control is performed to stop the operation of the engine-related auxiliary equipment and external auxiliary equipment, thereby compensating for the driving force difference and avoiding downshifting. be able to. In the continuously variable transmission, it is only necessary to change the gear ratio as much as necessary, and it can be optimized only by the engine and the transmission.
As a method of optimization, originally, the best combination is selected by measuring in advance the fuel consumption rate in the combination of the operation of all engine-related accessories and external accessories in the vehicle speed and target drive wheel torque in all regions, It should be controlled accordingly. In this case, considering the fuel efficiency and noise (engine speed),
External auxiliary machine → auxiliary machine with engine → gear transmission mechanism 14 of stepped transmission 2 → lockup mechanism 15 of stepped transmission 2
In this order, it is appropriate to switch the state from fuel consumption priority (auxiliary drive) to torque priority (auxiliary machine stopped). In other words, even when torque is prioritized (auxiliary is stopped), the external accessory that does not deteriorate the fuel consumption is given the highest priority, and the engine auxiliary accessory that does not deteriorate the noise (engine speed) is the next priority, and the lock that causes a large deterioration in fuel consumption. The up mechanism is the last. However, since there are various control restrictions depending on external accessories and engine-related accessories, control may not be possible.
The control methods, effects, and control restrictions of the external auxiliary machine, the engine-related auxiliary machine, and the stepped transmission 2 are as follows.
The external auxiliary machine includes a compressor 11 and an alternator 12 of an air conditioner 10. These external auxiliary machine control methods are normally operated unless the high gear stage of the stepped transmission 2 can be used or locked up if it is temporarily stopped. The compressor 11 of the air conditioner 10 has a problem that the torque is improved by the temporary stop as an effect, and the stop time is limited by the evaporator temperature or the like as a constraint. The alternator 12 has a problem that the torque is improved by the temporary stop as an effect, and the stop time is limited by the battery discharge as a restriction condition.
As the engine-related auxiliary equipment, there are an exhaust gas recirculation device 6 and a variable valve timing mechanism 7. The control method of these engine-accompanying auxiliary machines is an operation that gives priority to fuel consumption as much as possible. However, if the operation is given priority to torque, the high gear stage of the stepped transmission 2 can be used or the lockup mechanism 15 can be locked up. , Torque priority operation. The exhaust gas recirculation device 6 has a problem that fuel efficiency is improved as an effect, and as a restriction condition, it cannot be used due to freezing at a low intake air temperature, and cannot be used due to unstable combustion at a low water temperature. The variable valve timing mechanism 7 has an effect that the fuel efficiency is improved as a result of the fuel efficiency priority setting, and the restriction condition cannot be used due to unstable hydraulic pressure at low oil temperature, and cannot be used due to low oil pressure at low rotation or high oil temperature. is there. In addition, the variable valve timing mechanism 7 has an effect that the torque increases as a result of the torque priority setting, and cannot be used due to instability of the hydraulic pressure at low oil temperature, and cannot be used at low rotation or high oil temperature due to a decrease in hydraulic pressure. There's a problem.
The stepped transmission 2 includes a torque converter 13 and a gear transmission mechanism 14 and includes a lockup mechanism 15. The control method of the stepped transmission 2 uses the highest gear stage of the gear transmission mechanism 14 that locks up (couples) the lockup mechanism 15 as much as possible and can achieve the target drive wheel torque. The gear transmission mechanism 14 of the stepped transmission 2 can amplify the driving wheel torque by switching the gear stage as an effect, and is not particularly limited. The lockup mechanism 15 of the stepped transmission 2 has an effect of improving the fuel efficiency by the lockup, and cannot be used because the sound and vibration are generated at a low rotation and high torque as a constraint condition. The lockup mechanism 15 is equipped at a low gear stage. In many cases, slip lockup is not possible at low oil temperature due to instability of hydraulic pressure.
Regarding the priority order among external accessories, the time that external accessories can be stopped is limited, and the stop time also depends on the situation at that time (change based on the external load that is changed by the environment and human demand) Because they are different, there is no clear priority. Any external auxiliary machine can be stopped as long as it can be stopped.
Moreover, since the priority order in the engine-accompanying accessories varies depending on the characteristics, the fuel consumption rate at each engine speed and engine load should be determined in advance. For example, in the exhaust gas recirculation device 6 and the variable valve timing mechanism 7, even if the variable valve timing mechanism 7 is set to give priority to torque while the exhaust gas is recirculated by the exhaust gas recirculation device 6, the engine torque does not increase so much. Since the fuel consumption deteriorates, the exhaust gas recirculation device 6 should be stopped first (exhaust gas recirculation stop).

As described above, the control device 17 of the engine 1 sets the order of the switching timing of the external auxiliary machine, the engine-related auxiliary machine, and the driving / stopped state of the stepped transmission 2 in advance by the control unit 18. It has a function to change and control the throttle opening of the electronic throttle valve 3 in accordance with any state change of the external auxiliary machine, the engine-related auxiliary machine, or the stepped transmission 2. The throttle opening of the electronic throttle valve 3 is gradually increased, and when the predetermined throttle opening is reached, the external auxiliary machine, the engine auxiliary auxiliary machine, and the stepped transmission 2 are driven / stopped according to a preset switching timing order. Control is performed so as to sequentially change the state.
As a result, the control device 17 of the engine 1 can stepwise change the driving wheel torque set according to the relationship with the vehicle speed in response to an artificial operation of the accelerator pedal (torque request based on the accelerator opening). Thus, the throttle opening and the driving state of the auxiliary machinery can be brought into an optimum state in which fuel consumption, noise, and exhaust gas emission are balanced. As a result, for example, the torque change when changing from low load to high load is moderated to obtain a smooth acceleration feeling, or conversely, the torque change when changing from high load to low load is moderated. Further, it is possible to improve fuel efficiency by preventing shift hunting, or by using a gear step that is one step higher than in the prior art, or by locking up in steady running.
Further, the control device 17 of the engine 1 can increase the relative torque while keeping the throttle opening relatively small under the limited conditions, and can suppress an excessive accelerator operation. If the output torque of the engine 1 is required even when the drive torque is the same as when locked up at the third speed, as in the case of locking up at the fourth speed, it is not an excessive accelerator operation. It is also possible to travel with the throttle opening kept large.
The control means 18 sets the order of switching timing in the order of external accessories, engine-related accessories, and stepped transmission 2.
As a result, the control device 17 of the engine 1 raises the rank of the external auxiliary machine driven by the engine 1 so that the fuel consumption does not deteriorate even if it is stopped. On the other hand, the control device 17 of the engine 1 does not cause noise deterioration even when the engine is stopped by setting the rank of the engine-accompanying auxiliary machine to medium. In addition, the control device 17 of the engine 1 can reduce the frequency of the shift by lowering the rank of the stepped transmission 2, can suppress a large fluctuation of the engine 1 due to the shift, and prevent deterioration of fuel consumption. In addition, it is possible to suppress noise increase and exhaust gas deterioration. At this time, while the output torque of the engine 1 changes stepwise by orderly switching, the drive torque can be smoothly changed to increase in acceleration and decrease in deceleration. Further, in the embodiment, acceleration is exemplified, but at the time of deceleration, the order of the external accessory and the engine-related accessory is reversed, the order of the stepped transmission 2 is lowered, and the throttle control is performed, An effect can be obtained.
The engine-related accessory includes an exhaust gas recirculation device 6 and a variable valve timing mechanism 7. The control means 18 controls the exhaust gas recirculation device 6 to change the driving / stopped state before the variable valve timing mechanism 7.
Thereby, the control device 17 of the engine 1 can efficiently increase the torque by the variable valve timing mechanism 7, and can suppress deterioration of fuel consumption by coordinating with the state of the exhaust gas recirculation device 6.

The predetermined throttle opening determined by the control means 18 is a throttle opening set when the air amount becomes maximum, and is the minimum throttle opening (medium opening) among them. That is, it can be said that the throttle opening is in a state where the output torque of the engine 1 per revolution converges to a substantially constant value. Since the torque required to drive these external auxiliary devices such as the alternator 12, the compressor 11 of the air conditioner 10, the blower fan, or the fan motor of the radiator is known in advance, a throttle opening skip amount corresponding to the torque is set in advance. Therefore, it is possible to perform feedforward control in the change control of the throttle opening. Torque fluctuations can be kept small to match the desired torque.
Even if this torque is constant, the output power increases and the traveling speed increases as the engine speed increases. The torque change due to the change in the throttle opening and the auxiliary machinery that becomes the load torque are added, and the output torque is determined by the magnitude balance. Therefore, the torque can be increased even if the throttle opening is reduced. The engine 1 is operated with a small fluctuation range and a short cycle mainly in the middle range of the throttle opening, and the combustion efficiency is good, and purification is possible even if the catalyst capacity is small. Alternatively, noble metals used for the catalyst can be reduced.
The order of priority among the external accessories of the engine 1 is fluid. When the battery capacity is sufficiently satisfied or when the temperature is high, the alternator 12 stops before the compressor 11 and the blower fan of the air conditioner 10 (shown in the time chart of FIG. 2). When the battery capacity is low, or when using accessories such as nighttime, rain, or AV (acoustic video) equipment, the compressor 11 and the blower fan of the air conditioner 10 stop before the alternator 12 because the power consumption is large. Become.

In this embodiment, the engine auxiliary equipment is the exhaust gas recirculation device 6 and the variable valve timing mechanism 7, and the external auxiliary equipment is the compressor 11 and the alternator 12 of the air conditioner 10. However, in addition to this, the variable intake system, swirl Tumble control valves, various variable valve mechanisms, cylinder deactivation devices, air-fuel ratio control devices such as lean combustion, and the like can be controlled in the same way when torque is affected.
Further, in this embodiment, the engine generated torque is calculated from the accelerator opening and the vehicle speed, but more accurate control is possible by correcting the engine generated torque based on the atmospheric pressure, the intake air temperature, and the like. Furthermore, if the friction / viscous torque of each part of the drive system can be predicted by temperature or the like, more accurate control can be performed. Furthermore, if load information such as the alternator 12 and the compressor 11 of the air conditioner 10 is linearly obtained as an auxiliary machine torque, more accurate control is possible. Further, when controlling to the target engine generated torque, more precise control is possible by controlling not only the throttle opening but also the ignition timing.
Furthermore, in this embodiment, the operation of changing the phase of the variable valve timing mechanism 7 which is an engine-accompanying auxiliary device has been described so as to select a simple binary value (drive / stop). It is also possible to adopt a step structure or a structure that can be continuously changed so as to be stepless. Further, the variable valve timing mechanism 7 can be replaced with a variable valve lift mechanism, and may be configured to include both of them. Further, in this embodiment, the slow acceleration is taken as an example, but the present invention can also be applied to the slow deceleration by determining the order of the auxiliary machinery for the decreasing required torque. Furthermore, a conventional shift map (a map of speed and throttle opening) is basically unnecessary, but it can be combined only in a specific operating state or arbitrarily selected.

  The present invention relates to control of throttle opening and integrated engine output control including external auxiliary equipment and engine auxiliary equipment in a transient state, and relates to a stepped transmission, an electronic throttle valve, and various types of auxiliary power that affect engine torque. It can be applied to the control of a vehicle engine equipped with a machine.

It is a flowchart of the control apparatus of the engine which shows an Example. It is a time chart of the control apparatus of the engine which shows an Example. It is a block diagram of the control apparatus of the engine which shows an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Stepped transmission 3 Electronic throttle valve 6 Exhaust gas recirculation device 7 Variable valve timing mechanism 8 EGR valve 9 Timing control valve 10 Air conditioner 11 Compressor 12 Alternator 13 Torque converter 14 Gear transmission mechanism 15 Lock-up mechanism 16 Transmission control means 17 control device 18 control means

Claims (3)

A stepped transmission is added to the engine of the vehicle, and an external auxiliary machine driven by the engine and an electronic device that reflects the artificial operation of the accelerator pedal or can operate independently of the artificial operation of the accelerator pedal. An engine control apparatus comprising: an engine-related accessory that includes a throttle valve and that can change an output torque of the engine; and a control unit that controls the external accessory, the engine-related accessory, and a stepped transmission. The control means sets in advance the switching timing of the drive / stop state of the external auxiliary machine, the engine auxiliary auxiliary machine, and the stepped transmission, and any of these external auxiliary machine, engine auxiliary auxiliary machine, and stepped transmission is selected. The electronic throttle valve has a function of changing and controlling the throttle opening of the electronic throttle valve in accordance with the state change. The throttle opening of the valve is gradually increased, and when the predetermined throttle opening is reached, the switching of the driving / stopping state of the external auxiliary device, the engine-related auxiliary device, and the stepped transmission is sequentially performed according to the order of the switching timing. The engine control apparatus is characterized in that the throttle opening is adjusted so that a torque change due to the change in switching does not occur .   The engine control apparatus according to claim 1, wherein the control unit sets the order of switching timing in the order of an external accessory, an engine-accompanying accessory, and a stepped transmission.   The engine accessory includes an exhaust gas recirculation device and a variable valve timing mechanism, and the control means controls the exhaust gas recirculation device to change the driving / stopped state before the variable valve timing mechanism. The engine control device according to claim 2.

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