JP5252317B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control apparatus that improves the control of an automatic transmission when idle stop control is executed in a deceleration region in which a vehicle may stop while the vehicle is running in a vehicle with an idle stop function. It is.

  In a conventional vehicle with a general idle stop function, when the driver stops the vehicle, fuel injection is stopped (fuel cut) and the engine is automatically stopped, and then the driver starts the vehicle. When an operation to be performed (brake release operation, accelerator depression operation, etc.) is performed, the starter is automatically energized to restart the engine.

  Recently, with the aim of further improving fuel efficiency, it has become necessary to expand the idle stop region (fuel cut region) also in the deceleration region at a low speed that may cause the vehicle to stop while the vehicle is running. (See Patent Document 1).

  In general, the idle stop function is mounted on a vehicle in combination with an automatic transmission, and the automatic transmission is often composed of a torque converter and a transmission mechanism. Inside the speed change mechanism, a one-way clutch that restricts torque transmission in only one direction and a plurality of friction engagement elements (clutch and brake) for switching the speed ratio of the speed change mechanism are provided. By individually controlling the hydraulic pressure applied to the elements, the engagement and release of each friction engagement element are selectively switched to switch the speed ratio of the transmission mechanism (see Patent Documents 2 and 3).

JP-A-7-266932 JP 2002-89703 A JP 2009-275812 A

  By the way, when performing an idle stop (engine combustion stop) in a deceleration region during vehicle travel, when a restart request is generated during vehicle deceleration due to idle stop, it is necessary to quickly restart the engine and accelerate the vehicle. is there.

  However, when the engine is restarted at the time of vehicle deceleration due to idle stop while the vehicle is running and the vehicle is accelerated, the one-way clutch of the speed change mechanism changes suddenly from the idling state to the locked state (engaged state) and a shock is generated. There were drawbacks.

  That is, as shown in FIG. 4, when the vehicle is accelerated by restarting the engine in response to a restart request when the vehicle is decelerated, the input shaft rotation speed of the speed change mechanism is increased by the increase in the engine rotation speed after the engine restarts. When suddenly rising, the rotation speed (idling speed) of the one-way clutch suddenly drops and the one-way clutch is suddenly locked from the idling state, so that a shock is generated.

The shock generation mechanism will be described with reference to the alignment charts of FIGS.
When the vehicle decelerates due to an idle stop while the vehicle is running, the one-way clutch is idling as shown in the collinear diagram of FIG. 6, and the engine is restarted in this state to accelerate the vehicle. 5, the input shaft rotational speed of the speed change mechanism blows up and the output shaft rotational speed suddenly rises, causing the idling speed of the one-way clutch to suddenly drop and the one-way clutch to idle. Since the state suddenly becomes locked, a shock occurs.

  Therefore, the problem to be solved by the present invention is to prevent a shock due to a sudden lock (engagement) of the one-way clutch when a restart request is generated at the time of vehicle deceleration due to idle stop during vehicle deceleration and the engine is restarted. It is to provide a control device for a vehicle.

  In order to solve the above-mentioned problem, the invention according to claim 1 is directed to a transmission mechanism that shifts engine power and transmits it to the drive wheel side, a one-way clutch that restricts torque transmission in only one direction, and the transmission mechanism. And a plurality of friction engagement elements for switching the transmission ratio of the friction engagement elements, and selectively controlling engagement and release of each friction engagement element by individually controlling the hydraulic pressure applied to the plurality of friction engagement elements. In a vehicle control apparatus comprising a shift control means for switching to change a gear ratio of the transmission mechanism and an idle stop control means for controlling automatic stop and restart of the engine, the idle stop control means is configured to decelerate the vehicle. Means for stopping the combustion of the engine at a predetermined timing when an idle stop request is generated in a predetermined deceleration region that may lead to a vehicle stop during Means for restarting the engine when a restart request is generated when the vehicle is decelerated due to combustion stop (idle stop) of the engine, and the shift control means is configured when the idle stop request is generated during vehicle deceleration. OWC parallel clutch engagement control for engaging a friction engagement element (hereinafter referred to as “OWC parallel clutch”) provided in parallel with the one-way clutch of the speed change mechanism at a predetermined timing is executed.

  If the OWC parallel clutch engagement control for engaging the OWC parallel clutch is executed when an idle stop request is generated during vehicle deceleration as in the present invention, a restart request is generated when the vehicle is decelerated due to idle stop. When the engine is restarted, it is possible to restrain the one-way clutch from idling by OWC parallel clutch engagement control in advance, so that a shock due to a sudden lock (engagement) of the one-way clutch can be prevented.

  In the present invention, an idle stop (combustion stop of the engine) may be executed immediately when an idle stop request is generated during vehicle deceleration, but in this way, during the execution of the OWC parallel clutch engagement control. A restart request may occur. Until the OWC parallel clutch engagement control is completed, the engagement of the OWC parallel clutch is incomplete and the one-way clutch is still idling. Therefore, when the engine is restarted at this stage, the one-way clutch suddenly There is a possibility that a shock due to a serious lock may occur.

  As a countermeasure against this, when an idle stop request is generated during vehicle deceleration, the engine combustion is stopped by the idle stop control means after executing the OWC parallel clutch engagement control. good. In this way, since the one-way clutch is restrained from idling by the OWC parallel clutch engagement control, the idle stop can be executed, so the engine is restarted in response to the restart request when the vehicle is decelerated by the idle stop. Even if it makes it, the shock by the sudden lock | rock of a one-way clutch can be prevented reliably.

  Note that when an idle stop request (engine combustion stop) is executed immediately when an idle stop request is generated during vehicle deceleration, the OWC parallel clutch engagement control is executed when the vehicle is decelerated by idle stop. What is necessary is just to make it restart an engine after OWC parallel clutch engagement control is complete | finished when the restart request | requirement generate | occur | produces on the way. Even in this case, since the one-way clutch can be restrained from idling by the OWC parallel clutch engagement control, the idle stop can be executed, so that the shock due to the sudden lock of the one-way clutch at the time of engine restart can be ensured. Can be prevented.

  In addition, since the OWC parallel clutch engagement control is performed during vehicle deceleration, if the OWC parallel clutch is suddenly engaged by the OWC parallel clutch engagement control, the engine brake may suddenly start to be effective and a shock may occur. .

  As a countermeasure against this, it is preferable to gradually increase the hydraulic pressure supplied to the OWC parallel clutch so that the OWC parallel clutch is gradually engaged while slipping during execution of the OWC parallel clutch engagement control. . In this way, since the engagement force of the OWC parallel clutch can be gradually increased during execution of the OWC parallel clutch engagement control, the engine brake due to the engagement of the OWC parallel clutch starts to be gradually applied during vehicle deceleration. It is possible to prevent a shock from occurring when the engine brake starts to work.

  In order to quickly restart the engine in response to a restart request when the vehicle is decelerated due to idle stop, it is desirable to make the execution time of the OWC parallel clutch engagement control as short as possible. If the supply is started from a state in which the hydraulic pressure is completely released, the hydraulic pressure supply time required until the OWC parallel clutch is engaged becomes longer.

  Therefore, as in claim 5, the vehicle is provided with an idle stop prediction means for predicting the possibility of occurrence of an idle stop request during vehicle travel, and when the possibility of occurrence of an idle stop request is predicted by the idle stop prediction means. Then, it is preferable to execute the engagement standby control in which the hydraulic pressure is supplied and waits until the standby hydraulic pressure immediately before the OWC parallel clutch is engaged. In this way, before the idle stop request is generated, the hydraulic pressure of the OWC parallel clutch can be increased to the standby hydraulic pressure immediately before the engagement state is established by the engagement standby control. The execution time of the OWC parallel clutch engagement control to be performed can be shortened.

  In this case, as in the sixth aspect, the oil pressure command value may be set higher than the standby hydraulic pressure at the initial stage of the engagement standby control so that the OWC parallel clutch is rapidly filled with the hydraulic pressure up to the standby hydraulic pressure. In this way, the execution time of the engagement standby control can be shortened.

  Further, as in claim 7, the idle stop prediction means may predict the possibility of occurrence of an idle stop request based on at least the vehicle speed. As the vehicle speed decreases, the possibility of a vehicle stop increases, so the possibility of an idle stop request can be predicted from the vehicle speed.

  Alternatively, the idle stop predicting means may predict the possibility of an idle stop request based on the vehicle speed and the deceleration. The greater the deceleration, the shorter the time until the vehicle stops.If the possibility of an idle stop request is predicted in consideration of the deceleration in addition to the vehicle speed, the idle stop request can be generated at a more appropriate timing. The possibility can be predicted.

  Further, as in claim 9, the OWC parallel clutch that has been engaged by the OWC parallel clutch engagement control may be released at a predetermined time after the vehicle is stopped or the engine is restarted. After the vehicle stops, the input / output shaft of the speed change mechanism, the one-way clutch, and the OWC parallel clutch are all stopped. Therefore, even if the OWC parallel clutch is released, a shock due to a sudden lock of the one-way clutch occurs when the engine is restarted. do not do. Further, if the OWC parallel clutch is released at a predetermined time after the engine is restarted, the gear ratio of the transmission mechanism can be sequentially switched according to the acceleration state of the vehicle after the engine is restarted.

  In this case, it is preferable that the OWC parallel clutch is released when the OWC parallel clutch starts to transmit torque after the engine is restarted by the idle stop control means. In this way, it is possible to release the OWC parallel clutch at an optimal timing after the engine is restarted and to start a shift according to the traveling state of the vehicle.

  Specifically, as in claim 11, after the engine is restarted by the idle stop control means, the engine rotational speed is the turbine rotational speed of a torque converter provided between the output shaft of the engine and the input shaft of the transmission mechanism. The OWC parallel clutch may be released when exceeded. When the engine rotation speed exceeds the turbine rotation speed after engine restart, the engine torque drives the input shaft (turbine shaft of the torque converter) of the speed change mechanism, so the OWC parallel clutch begins to transmit torque. And the OWC parallel clutch is released.

  Alternatively, as described in claim 12, the OWC parallel clutch may be released when the state where the engine rotational speed is equal to or higher than a predetermined value continues for a predetermined time after the engine is restarted by the idle stop control means. For example, depending on the running state of the vehicle after restarting the engine, it may take a long time for the engine speed to exceed the turbine speed after the engine is restarted. If the OWC parallel clutch is disengaged for more than an hour, it is determined that the shock due to the lock of the one-way clutch no longer occurs, and the OWC parallel clutch is disengaged so that a shift according to the running state of the vehicle is possible. To do.

  Further, as in the thirteenth aspect, when the engine rotational speed exceeds the turbine rotational speed of the torque converter after the engine is restarted by the idle stop control means, or when the engine rotational speed is higher than a predetermined value for a predetermined time or longer. The OWC parallel clutch may be released at an earlier timing. In this way, it is possible to more accurately determine the release timing of the OWC parallel clutch.

FIG. 1 is a schematic configuration diagram of an entire automatic transmission according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the mechanical configuration of the automatic transmission. FIG. 3 is a diagram showing a combination of clutch / brake engagement / release for each gear position. FIG. 4 is a time chart illustrating an example of control when an idle stop request is generated during vehicle deceleration. FIG. 5 is a collinear diagram at the first speed of the D range. FIG. 6 is a collinear diagram at the time of deceleration of the first speed in the D range. FIG. 7 is a collinear diagram when the OWC parallel clutch engagement control is performed at the time of deceleration in the first speed of the D range. FIG. 8 is a time chart for explaining an example of the OWC parallel clutch engagement control. FIG. 9 is a flowchart for explaining the flow of processing of the idle stop control routine. FIG. 10 is a flowchart for explaining the processing flow of the engagement standby control start timing determination routine. FIG. 11 is a diagram conceptually illustrating a map of the correction value A used for calculating the engagement standby control start timing determination threshold value. FIG. 12 is a flowchart for explaining the processing flow of the idle stop condition determination routine. FIG. 13 is a flowchart for explaining the flow of processing of the engine restart condition determination routine. FIG. 14 is a flowchart for explaining the processing flow of the engagement standby control execution routine. FIG. 15 is a flowchart for explaining the flow of processing of the OWC parallel clutch engagement control execution routine. FIG. 16 is a flowchart for explaining the flow of processing of the OWC parallel clutch release routine.

Hereinafter, an embodiment embodying a mode for carrying out the present invention will be described.
First, a schematic configuration of the automatic transmission 11 will be described with reference to FIGS. 1 and 2.
As shown in FIG. 2, an input shaft 13 of a torque converter 12 is connected to an output shaft of an engine (not shown), and a hydraulically driven transmission gear mechanism 15 (speed change) is connected to the output shaft 14 of the torque converter 12. Mechanism). Inside the torque converter 12, a pump impeller 31 and a turbine runner 32 constituting a fluid coupling are provided to face each other, and a stator 33 for rectifying the flow of oil is provided between the pump impeller 31 and the turbine runner 32. It has been. The pump impeller 31 is connected to the input shaft 13 of the torque converter 12, and the turbine runner 32 is connected to the output shaft 14 of the torque converter 12.

  The torque converter 12 is provided with a lock-up clutch 16 for engaging or disengaging between the input shaft 13 side and the output shaft 14 side. The engine output torque is transmitted to the transmission gear mechanism 15 via the torque converter 12, and is shifted by a plurality of gears (front planetary gear 23, rear planetary gear 22 and the like) of the transmission gear mechanism 15 to drive the vehicle drive wheels (front wheels or Is transmitted to the rear wheels. The transmission gear mechanism 15 is provided with a plurality of clutches RC, HC, LC and brakes B0, B1, which are a plurality of friction engagement elements for switching a plurality of shift stages, and a one-way clutch 34 (OWC). As shown in FIG. 3, the gear ratio is switched by switching the engagement / release of the clutches RC, HC, LC and the brakes B0, B1 by hydraulic pressure and switching the combination of gears for transmitting power. It is like that.

  Here, the one-way clutch 34 regulates torque transmission only in one direction (vehicle driving direction), and a brake B1 (OWC parallel clutch) is provided in parallel with the one-way clutch 34.

  FIG. 3 shows a combination of engagement of the clutches RC, HC, LC and brakes B0, B1 of the 4-speed automatic transmission. The circles are held in the engaged state (torque transmission state) at the gear stage. The clutch and brake are shown, and the unmarked state shows the released state.

  For example, when the accelerator is depressed in the D range (drive range), the speed is upshifted to the first speed, the second speed, the third speed, and the fourth speed as the vehicle speed increases. In the shift from the first speed to the second speed, B0 is newly engaged from the LC engagement state. In the shift from the second speed to the third speed, B0 is released from the engaged state of LC and B0, and HC is newly engaged. In the shift from the 3rd speed to the 4th speed, the LC is released from the engaged state of the HC and the LC, and B0 is newly engaged. In the L range (low range), the LC and B1 are engaged. In the R range (reverse range), the RC and B1 are engaged. In the P range (parking range) and N range (neutral range), all the friction engagement elements are released.

  As shown in FIG. 1, the transmission gear mechanism 15 is provided with a hydraulic pump 18 driven by engine power and an electric hydraulic pump 24 driven by a motor (not shown). During engine operation, hydraulic pressure is supplied by the engine-driven hydraulic pump 18, and during idle stop, which will be described later, the engine-driven hydraulic pump 18 stops, so that the hydraulic pressure is supplied by the electric hydraulic pump 24. It has become.

  A hydraulic control circuit 17 is provided in an oil pan (not shown) that stores hydraulic oil (oil). The hydraulic control circuit 17 includes a line pressure control circuit 19, an automatic transmission control circuit 20, a lock-up control circuit 21, a manual switching valve 26, and the like. The hydraulic oil pumped up from the oil pan by the hydraulic pump 18 is line pressure controlled. This is supplied to the automatic transmission control circuit 20 and the lockup control circuit 21 via the circuit 19.

  The line pressure control circuit 19 is provided with a hydraulic pressure control valve (not shown) for controlling the hydraulic pressure from the hydraulic pump 18 to a predetermined line pressure. The automatic transmission control circuit 20 has a transmission gear mechanism. A plurality of shift hydraulic control valves (not shown) for controlling the hydraulic pressure supplied to the 15 clutches RC, HC, LC and the brakes B0, B1 are provided. The lockup control circuit 21 is provided with a lockup control hydraulic control valve (not shown) for controlling the hydraulic pressure supplied to the lockup clutch 16.

  A manual switching valve 26 that is switched in conjunction with the operation of the shift lever 25 is provided between the line pressure control circuit 19 and the automatic transmission control circuit 20. When the shift lever 25 is operated to the N range (neutral range) or the P range (parking range), even if the power supply to the hydraulic control valve of the automatic transmission control circuit 20 is stopped (OFF), The hydraulic pressure supplied to the transmission gear mechanism 15 by the manual switching valve 26 is switched so that the transmission gear mechanism 15 is in a neutral state.

  On the other hand, the engine is provided with an engine rotation speed sensor 27 that detects an engine rotation speed Ne (the rotation speed of the input shaft 13 of the torque converter 12). The transmission gear mechanism 15 has an input shaft rotation speed of the transmission gear mechanism 15. An input shaft rotational speed sensor 28 (turbine rotational speed sensor) that detects Nt (turbine rotational speed Nt, which is the rotational speed of the output shaft 14 of the torque converter 12), and an output that detects the output shaft rotational speed No of the transmission gear mechanism 15. A shaft rotation speed sensor 29 is provided.

  Output signals of these various sensors are input to an automatic transmission electronic control circuit (hereinafter referred to as “AT-ECU”) 30. The AT-ECU 30 is composed mainly of a microcomputer and functions as a shift control means in the claims by executing each routine stored in a built-in ROM (storage medium). Energizing each hydraulic control valve of the automatic transmission control circuit 20 according to the operating position of the shift lever 25 and the operating conditions (throttle opening, vehicle speed, etc.) so that the transmission of the transmission gear mechanism 15 is executed according to the transmission pattern. By controlling the hydraulic pressure applied to each clutch RC, HC, LC and each brake B0, B1 of the transmission gear mechanism 15, as shown in FIG. 3, each clutch RC, HC, LC and each brake B0. , B1 is switched between engagement and disengagement, and the gear ratio of the transmission gear mechanism 15 is switched by switching the combination of gears that transmit engine power. Obtain.

  Furthermore, the AT-ECU 30 is connected to the engine control device 37 and transmits and receives control signals and the like between them. When an idle stop signal is transmitted from the engine control device 37 to the AT-ECU 30, an OWC parallel clutch (brake B1) provided in parallel with a one-way clutch (hereinafter referred to as “OWC”) 34 at a predetermined timing. ) Is engaged.

  The engine control device 37 is configured by one or a plurality of ECUs (for example, an engine ECU and an idle stop ECU). The engine control device 37 includes various sensors (for example, an air flow meter, a throttle opening sensor, an intake pipe pressure sensor, an exhaust gas sensor, a coolant temperature sensor, a crank angle sensor, a brake switch, an accelerator sensor, a vehicle speed sensor) Etc.) is input.

  During engine operation, the engine control device 37 controls the fuel injection amount, the intake air amount (throttle opening), the ignition timing, and the like according to the operation state detected by the various sensors. Further, the engine control device 37 also functions as an idle stop control means in the claims, and monitors whether or not an idle stop request is generated during engine operation (idle stop condition is satisfied). When the request is generated, the fuel injection is stopped (fuel cut), and the combustion of the engine 11 is automatically stopped (idle stop).

  In the present embodiment, in order to expand the idle stop region (fuel cut region), an idle stop request is generated even in a low-speed deceleration region that may cause the vehicle to stop while the vehicle is running. Specifically, it is determined under the following conditions whether or not a predetermined deceleration state that may cause the vehicle to stop during traveling of the vehicle is reached (whether or not an idle stop request is generated). For example, (1) Accelerator fully closed (Throttle fully closed), (2) While depressing the brake, (3) Determining whether the vehicle is in the low speed range below the specified vehicle speed, and satisfying these conditions (1) to (3) If all the conditions are satisfied, it is determined that the vehicle is in a predetermined deceleration state that may cause the vehicle to stop. Needless to say, the method for determining the predetermined deceleration state that may result in the vehicle stopping may be changed as appropriate.

  When it is determined that the vehicle is in a predetermined deceleration state that may cause the vehicle to stop during deceleration, it is determined that an idle stop request has occurred, fuel injection is stopped (fuel cut), and engine combustion is automatically performed. Stop (idle stop). After that, during the idle stop period (during engine descent due to idle stop or after engine rotation has stopped), the driver tries to reaccelerate or start the vehicle (for example, release of brake depression, accelerator depression, shift lever When an operation to the drive range is performed, a restart request is generated, fuel injection is restarted, and the engine is restarted. In addition, the engine may be restarted when a restart request is generated from a control system of an in-vehicle device such as a battery charge control system or an air conditioner.

  By the way, when performing an idle stop (engine combustion stop) during vehicle deceleration, if a restart request is generated during vehicle deceleration due to idle stop, it is necessary to quickly restart the engine and accelerate the vehicle.

  However, in the conventional system, when the engine is restarted at the time of vehicle deceleration due to idle stop during vehicle deceleration and the vehicle is accelerated, the OWC 34 (one-way clutch) of the transmission gear mechanism 15 is suddenly changed from the idling state to the locked state (engaged state). However, there was a drawback that a shock occurred.

  That is, as shown in FIG. 4, when the vehicle is accelerated by restarting the engine in response to a restart request when the vehicle is decelerated, the input shaft of the transmission gear mechanism 15 is rotated by the increase in the engine rotation speed after the engine is restarted. When the speed (turbine rotational speed of the torque converter 12) rapidly increases, the rotational speed (idling speed) of the OWC 34 suddenly drops and the OWC 34 is suddenly locked from the idling state, so that a shock is generated.

  The shock generation mechanism will be described with reference to the alignment charts of FIGS. In the alignment chart, FrS is a front planetary gear_sun gear, FrC is a front planetary gear_carrier, FrC is a front planetary gear_ring gear, RrS is a rear planetary gear_sun gear, RrC is a rear planetary gear_carrier, and RrC is a rear planetary gear_ring gear.

  When the vehicle is decelerated due to an idle stop while the vehicle is decelerating, the deceleration state shown in the collinear chart of FIG. 6 is established and the OWC 34 is idling. Therefore, if the engine is restarted in this state and the vehicle is accelerated, 5, the input shaft rotation speed of the transmission gear mechanism 15 (turbine rotation speed of the torque converter 12) is blown up and the output shaft rotation speed of the transmission gear mechanism 15 is rapidly increased. As a result, the idling speed of the OWC 34 suddenly drops and the OWC 34 is suddenly locked from the idling state, so that a shock occurs.

  Therefore, in this embodiment, when an idle stop request is generated during vehicle deceleration, the OWC parallel clutch B1 provided in parallel with the OWC 34 of the transmission gear mechanism 15 is engaged as shown in the collinear diagram of FIG. The OWC parallel clutch engagement control is executed. In this way, when a restart request is generated when the vehicle is decelerated due to idle stop and the engine is restarted, it is possible to restrain the OWC 34 from idling in advance by the OWC parallel clutch engagement control. , Shock due to abrupt locking (fastening) of the OWC 34 can be prevented.

  In the present invention, an idle stop (combustion stop of the engine) may be executed immediately when an idle stop request is generated during vehicle deceleration, but in this way, during the execution of the OWC parallel clutch engagement control. A restart request may occur. Until the OWC parallel clutch engagement control is completed, the engagement of the OWC parallel clutch B1 is incomplete (slip state), and the OWC 34 is still idling. When the engine is restarted at this stage, There is a possibility that a shock due to a sudden lock of the OWC 34 may occur.

  As a countermeasure, in this embodiment, when an idle stop request is generated during vehicle deceleration, idle stop (engine combustion stop) is started after executing OWC parallel clutch engagement control. In this way, since the OWC 34 is restrained from idling by the OWC parallel clutch engagement control, the idle stop can be executed, so that the engine is restarted in response to the restart request when the vehicle is decelerated by the idle stop. However, it is possible to reliably prevent a shock due to a sudden lock of the OWC 34.

  In addition, when an idle stop (engine combustion stop) is executed immediately when an idle stop request is generated during vehicle deceleration, a restart request is generated during execution of the OWC parallel clutch engagement control during vehicle deceleration due to idle stop. The engine may be restarted after the OWC parallel clutch engagement control is finished. Even in this case, it is possible to execute idle stop after restraining the OWC 34 from idling by the OWC parallel clutch engagement control, so that it is possible to reliably prevent a shock caused by a sudden lock of the OWC 34 when the engine is restarted. .

  In addition, since the OWC parallel clutch engagement control is performed during the vehicle deceleration, if the OWC parallel clutch B1 is suddenly engaged by the OWC parallel clutch engagement control, the engine brake may suddenly start and a shock may occur. is there.

  As a countermeasure, in this embodiment, the hydraulic pressure supplied to the OWC parallel clutch B1 is gradually increased so that the OWC parallel clutch B1 is gradually engaged while slipping during execution of the OWC parallel clutch engagement control ( (See FIG. 8). In this way, since the engagement force of the OWC parallel clutch B1 can be gradually increased during the execution of the OWC parallel clutch engagement control, the engine brake due to the engagement of the OWC parallel clutch B1 is gradually reduced during vehicle deceleration. The effect can be started and a shock can be prevented from occurring at the beginning of working of the engine brake.

  Further, in order to restart the engine promptly in response to a restart request at the time of vehicle deceleration due to idle stop, it is desirable to shorten the execution time of the OWC parallel clutch engagement control as much as possible, but the hydraulic pressure to the OWC parallel clutch B1 Is started from a state in which the hydraulic pressure is completely released, the hydraulic pressure supply time required until the OWC parallel clutch B1 is engaged is lengthened.

  Therefore, in this embodiment, when the engine control device 37 is equipped with a function as an idle stop prediction means for predicting the possibility of occurrence of an idle stop request during traveling of the vehicle, the possibility of occurrence of an idle stop request is predicted. In addition, the engagement standby control is performed in which the hydraulic pressure is supplied to the standby hydraulic pressure immediately before the OWC parallel clutch B1 is brought into an engaged state to wait (see FIG. 8). In this way, the hydraulic pressure of the OWC parallel clutch B1 can be increased to the standby hydraulic pressure immediately before the engagement state is established by the engagement standby control before the idle stop request is generated. The execution time of the OWC parallel clutch engagement control to be executed can be shortened.

  Further, in the present embodiment, as shown in FIG. 8, the command hydraulic pressure of the OWC parallel clutch B1 is set to a quick filling hydraulic pressure higher than the standby hydraulic pressure at the initial stage of the engagement standby control, so that the OWC parallel clutch B1 has a hydraulic pressure up to the standby hydraulic pressure. Is to be filled quickly. In this way, the execution time of the engagement standby control can be shortened.

  In the present embodiment, the possibility of occurrence of an idle stop request is predicted based on at least the vehicle speed. As the vehicle speed decreases, the possibility of a vehicle stop increases, so the possibility of an idle stop request can be predicted from the vehicle speed.

  Furthermore, the possibility of an idle stop request may be predicted based on the vehicle speed and the deceleration. The greater the deceleration, the shorter the time until the vehicle stops.If the possibility of an idle stop request is predicted in consideration of the deceleration in addition to the vehicle speed, the idle stop request can be generated at a more appropriate timing. The possibility can be predicted.

  Further, in this embodiment, the OWC parallel clutch B1 that has been engaged by the OWC parallel clutch engagement control is released at a predetermined time after the vehicle is stopped or the engine is restarted. After the vehicle is stopped, the input / output shaft of the transmission gear mechanism 15, the OWC 34, and the OWC parallel clutch B1 are all stopped. Therefore, even if the OWC parallel clutch B1 is released, the shock due to the sudden lock of the OWC 34 when the engine is restarted. Does not occur. Further, if the OWC parallel clutch B1 is released at a predetermined time after the engine is restarted, the gear ratio of the transmission gear mechanism 15 can be sequentially switched according to the acceleration state of the vehicle after the engine is restarted.

  In this case, it is preferable that the OWC parallel clutch B1 is released when the OWC parallel clutch B1 starts to transmit torque after the engine is restarted. In this way, it is possible to release the OWC parallel clutch B1 at an optimal timing after the engine is restarted and to start a shift according to the traveling state of the vehicle.

  Specifically, the release timing of the OWC parallel clutch B1 may be when the engine rotation speed exceeds the turbine rotation speed of the torque converter 12 (the input shaft rotation speed of the transmission gear mechanism 15) after the engine is restarted. When the engine rotation speed exceeds the turbine rotation speed after engine restart, the engine torque drives the input shaft 13 of the transmission gear mechanism 15 (the output shaft 14 of the torque converter 12), and therefore the OWC parallel clutch B1 Is determined to have started to transmit torque, and the OWC parallel clutch B1 is released.

  Furthermore, the OWC parallel clutch may be released when the state where the engine speed is equal to or higher than a predetermined value continues for a predetermined time or longer after the engine is restarted. For example, depending on the running state of the vehicle after restarting the engine, it may take a long time for the engine speed to exceed the turbine speed after the engine is restarted. If the OWC parallel clutch B1 is disengaged for more than a certain period of time, it is determined that the shock due to the lock of the OWC 34 has stopped, and the OWC parallel clutch B1 is disengaged to allow gear shifting according to the running state of the vehicle. It is what.

  The idle stop control of the present embodiment described above is executed by the AT-ECU 30 and / or the engine control device 37 according to the routines of FIGS. The processing contents of these routines will be described below.

[Idle stop control routine]
The idle stop control routine of FIG. 9 is repeatedly executed during the power-on period of the AT-ECU 30 and the engine control device 37 (while the ignition switch is on). When this routine is started, first, at step 101, it is determined whether or not it is the engagement standby control start timing based on whether or not the engagement standby control start flag is ON. Here, the engagement standby control start flag is a flag that is switched ON / OFF by an engagement standby control start timing determination routine of FIG. 10 described later. An idle stop request is generated based on the vehicle speed and deceleration (idle stop condition). When the possibility of establishment is predicted, the engagement standby control start flag is set to ON. If it is determined in step 101 that the engagement standby control start flag is OFF, the process waits until it is turned ON.

  Thereafter, when the engagement standby control start flag is turned on, it is determined that the timing for starting the engagement standby control has come, and the routine proceeds to step 102 where an engagement standby control execution routine of FIG. The combined standby control is started, and the hydraulic pressure of the OWC parallel clutch B1 is increased to the standby hydraulic pressure just before the engagement state. Thereafter, the process proceeds to step 103 to determine whether or not the engagement standby control start flag is maintained ON. If the engagement standby control start flag is switched OFF, it is determined that the idle stop is not executed. Then, the process proceeds to step 110, where an OWC parallel clutch release routine of FIG. 16 described later is executed to release the hydraulic pressure of the OWC parallel clutch B1 and release the OWC parallel clutch B1.

  On the other hand, if it is determined in step 103 that the engagement standby control start flag is maintained ON, the process proceeds to step 104, and the idle idle condition is determined based on the processing result of the idle stop condition determination routine of FIG. It is determined whether or not the stop condition is satisfied (idle stop request is generated). If the idle stop condition is not satisfied, the process returns to the determination process in step 103.

  Thereafter, when the idle stop condition is satisfied, the routine proceeds to step 105, where an OWC parallel clutch engagement control execution routine of FIG. 15 described later is executed, and the oil pressure of the OWC parallel clutch B1 is gradually increased to the oil pressure at which the engagement state is established. The OWC parallel clutch B1 is lifted and gradually engaged while slipping.

  Thereafter, the routine proceeds to step 106, where fuel injection is stopped (fuel cut), and engine combustion is stopped (idle stop). Then, in the next step 107, it is determined whether or not the engine restart condition is satisfied (restart request is generated) based on the processing result of the engine restart condition determination routine of FIG. If is not established, the system waits until the engine restart condition is established.

  Thereafter, when the engine restart condition is satisfied, the routine proceeds to step 108, where fuel injection is resumed to restart the engine. After this, the routine proceeds to step 109, where it is determined whether (1) the engine speed exceeds the turbine speed, or (2) whether the engine speed has exceeded a predetermined value for a predetermined time or longer. It is determined whether or not the release timing of B1 is reached, and the process waits until either of the above conditions (1) and (2) is satisfied.

Thereafter, when either of the above conditions (1) and (2) is satisfied, it is determined that the timing for releasing the OWC parallel clutch B1 is reached, and the routine proceeds to step 110, where the OWC parallel clutch release routine of FIG. To release the hydraulic pressure of the OWC parallel clutch B1 and release the OWC parallel clutch B1.
If the vehicle stops before the engine restart condition is satisfied, the OWC parallel clutch B1 may be released when the vehicle stops.

[Engagement standby control start timing determination routine]
The engagement standby control start timing determination routine of FIG. 10 is repeatedly executed at a predetermined cycle during engine operation, and the standby state for engagement is predicted based on the vehicle speed and the deceleration as described below to predict the possibility of establishment of the idle stop condition. The control start timing is determined. This routine serves as idle stop prediction means in the claims.

  When this routine is started, first, at step 201, it is determined whether or not the accelerator is stepped on. If the accelerator is stepped on, it is not the timing for starting the engagement standby control (the possibility that the idle stop condition is satisfied). (No prediction is made), the process proceeds to step 205, and the engagement standby control start flag is maintained OFF (or reset).

On the other hand, if it is determined in step 201 that the accelerator is not depressed (accelerator fully closed), the routine proceeds to step 202, where the engagement standby control start timing determination threshold is set to the idle stop determination threshold. The correction value A is added and set.
Engagement standby control start timing judgment threshold
= Idle stop judgment threshold + Correction value A

  In this embodiment, an idle stop determination threshold value for the vehicle speed is set, and this idle stop determination threshold value is corrected with a correction value A corresponding to the deceleration to set an engagement standby control start timing determination threshold value. To do. At this time, the correction value A is calculated using a map having the deceleration shown in FIG. 11 as a parameter. The calculation map of the correction value A in FIG. 11 is set so that the greater the deceleration, the shorter the time until the idle stop condition is satisfied, and the greater the deceleration, the larger the correction value A. Yes.

  Note that a map for calculating the engagement standby control start timing determination threshold value using the vehicle speed and the deceleration as parameters is set, and this map is used to determine the engagement standby control start timing according to the vehicle speed and the deceleration. A value may be calculated.

  After calculating the engagement standby control start timing determination threshold value, the process proceeds to step 203, and whether or not the detected vehicle speed has become equal to or less than the engagement standby control start timing determination threshold value (whether the possibility of establishment of the idle stop condition has been predicted). If the detected vehicle speed is not less than or equal to the engagement standby control start timing determination, it is determined that it is not the engagement standby control start timing (the possibility that the idle stop condition is satisfied is not predicted), and the step Proceeding to 205, the engagement standby control start flag is maintained OFF (or reset).

  On the other hand, if it is determined in step 203 that the detected vehicle speed is equal to or lower than the engagement standby control start timing determination threshold value, it is the engagement standby control start timing (the possibility that the idle stop condition is satisfied is predicted. In step 204, the engagement standby control start flag is set to ON.

[Idle stop condition judgment routine]
The idle stop condition determination routine of FIG. 12 is repeatedly executed at a predetermined cycle during engine operation, and determines whether the idle stop condition is satisfied (idle stop request is generated) as follows.

  First, in step 301, it is determined whether or not the accelerator is stepped on. If the accelerator is stepped on, the process proceeds to step 305 and it is determined that the idle stop condition is not satisfied. On the other hand, if it is determined in step 301 that the accelerator is not depressed (accelerator fully closed), the process proceeds to step 302 to determine whether or not the brake is depressed. Proceeding to 305, it is determined that the idle stop condition is not satisfied.

  On the other hand, if it is determined in step 302 that the brake is being depressed, the process proceeds to step 303, in which it is determined whether the detected vehicle speed is equal to or lower than the idle stop determination threshold value, and the detected vehicle speed is determined to be an idle stop. If it is not below the threshold value, the routine proceeds to step 305, where it is determined that the idle stop condition is not satisfied.

  On the other hand, if it is determined in step 303 that the detected vehicle speed is equal to or lower than the idle stop determination threshold value, the process proceeds to step 304 and it is determined that the idle stop condition is satisfied.

[Engine restart condition judgment routine]
The engine restart condition determination routine of FIG. 13 is repeatedly executed at a predetermined cycle during idle stop, and determines whether the engine restart condition is satisfied as follows.

First, in step 401, it is determined whether or not the brake is depressed. If the brake is depressed, the process proceeds to step 404 and it is determined that the engine restart condition is not satisfied.
On the other hand, if it is determined in step 401 that the brake is not depressed, the process proceeds to step 402, where it is determined whether or not the accelerator is depressed. If the accelerator is not depressed, the process proceeds to step 404 and the engine It is determined that the restart condition is not satisfied.

  On the other hand, if it is determined in step 402 that the accelerator is depressed, the process proceeds to step 403 and it is determined that the engine restart condition is satisfied.

[Engagement standby control execution routine]
The engagement standby control execution routine of FIG. 14 is a subroutine executed in step 102 of the idle stop control routine of FIG. 9 when the engagement standby control start flag is set to ON. Engagement standby control is executed to increase the hydraulic pressure of the parallel clutch B1 to the standby hydraulic pressure just before the engagement state.

  First, in step 501, the command hydraulic pressure of the OWC parallel clutch B1 is set to a quick charging hydraulic pressure that is higher than the standby hydraulic pressure immediately before the engagement state, and the OWC parallel clutch B1 is rapidly charged up to the standby hydraulic pressure. In the next step 502, it is determined whether or not a predetermined time (preset rapid execution time) has elapsed since the start of rapid filling, and the rapid filling is continued until the predetermined time has elapsed.

Thereafter, when a predetermined time has elapsed from the start of rapid filling, it is determined that the oil pressure of the OWC parallel clutch B1 has increased to near the standby oil pressure, and the process proceeds to step 503 to set the command oil pressure of the OWC parallel clutch B1 to the standby oil pressure. Thus, the process shifts from the rapid filling to the standby hydraulic pressure holding, and the hydraulic pressure of the OWC parallel clutch B1 is held at the standby hydraulic pressure just before the engagement state.
[OWC parallel clutch engagement control execution routine]
The OWC parallel clutch engagement control execution routine of FIG. 15 is a subroutine that is executed in step 105 of the idle stop control routine of FIG. 9 when the idle stop condition is satisfied. The hydraulic pressure is gradually increased from the standby hydraulic pressure to the engaged hydraulic pressure, and the OWC parallel clutch B1 is gradually engaged while being slipped.

First, in step 601, the current command hydraulic pressure of the OWC parallel clutch B1 is increased by a predetermined pressure increase value from the previous command hydraulic pressure.
Current command oil pressure = previous command oil pressure + pressure increase value Here, the initial value of the command oil pressure is the standby oil pressure.

  Thereafter, the process proceeds to step 602, where it is determined whether or not the engagement of the OWC parallel clutch B1 has been completed based on whether or not the rotational speed of the OWC 34 has reached 0 rpm, and until the rotational speed of the OWC 34 has reached 0 rpm, step 601 is performed. The above process is repeated at a predetermined cycle, and the process of increasing the command hydraulic pressure of the OWC parallel clutch B1 by a pressure increase value at a predetermined cycle is repeated. Thereafter, when the rotational speed of the OWC 34 becomes 0 rpm, it is determined that the engagement of the OWC parallel clutch B1 is completed, and this routine is finished.

[OWC parallel clutch release routine]
The OWC parallel clutch release routine of FIG. 16 is a subroutine executed at step 110 of the idle stop control routine of FIG. 9 when the release timing of the OWC parallel clutch B1 is reached. When this routine is started, in step 701, the command hydraulic pressure of the OWC parallel clutch B1 is set to 0 MPa, the hydraulic pressure of the OWC parallel clutch B1 is released, and the OWC parallel clutch B1 is released.

  In the present embodiment described above, the OWC parallel clutch engagement control for engaging the OWC parallel clutch B1 is executed when an idle stop request is generated during vehicle deceleration. When a request is generated and the engine is restarted, the OWC 34 can be restrained in advance so that the OWC 34 does not idle by the OWC parallel clutch engagement control, and a shock due to a sudden lock (fastening) of the OWC 34 can be prevented.

  The present invention is not limited to the above-described embodiment, and for example, the configuration of the transmission gear mechanism 15, the number of shift stages, the relationship between engagement / release of friction engagement elements and the shift stages, and the like may be changed as appropriate. Various modifications can be made without departing from the spirit of the invention.

  DESCRIPTION OF SYMBOLS 11 ... Automatic transmission, 12 ... Torque converter, 15 ... Transmission gear mechanism (transmission mechanism), 16 ... Lock-up clutch, 17 ... Hydraulic control circuit, 18 ... Engine-driven hydraulic pump, 20 ... Automatic transmission control circuit, 24 DESCRIPTION OF SYMBOLS ... Electric hydraulic pump, 25 ... Shift lever, 27 ... Engine rotational speed sensor, 28 ... Input shaft rotational speed sensor (turbine rotational speed sensor), 29 ... Output shaft rotational speed sensor, 30 ... AT-ECU (hydraulic control means) ), 37 ... Engine control device (idle stop control means, idle stop prediction means), RC, HC, LC ... clutch (friction engagement element), B0 ... brake (friction engagement element), B1 ... brake (friction engagement) Element, OWC parallel clutch)

Claims (13)

A transmission mechanism that shifts engine power and transmits it to the drive wheel side is provided with a one-way clutch that restricts torque transmission in only one direction, and a plurality of friction engagement elements for switching the transmission ratio of the transmission mechanism. And
Shift control means for selectively switching engagement and disengagement of each friction engagement element by individually controlling the hydraulic pressure applied to the plurality of friction engagement elements, and switching a gear ratio of the transmission mechanism;
In a vehicle control device comprising idle stop control means for controlling automatic stop and restart of the engine,
The idle stop control means includes: means for stopping combustion of the engine at a predetermined timing when an idle stop request is generated in a predetermined deceleration region that may lead to vehicle stop during vehicle deceleration; and combustion stop of the engine Means for restarting the engine when a restart request occurs during vehicle deceleration by
The shift control means engages a friction engagement element (hereinafter referred to as “OWC parallel clutch”) provided in parallel with the one-way clutch of the transmission mechanism at a predetermined timing when the idle stop request is generated during vehicle deceleration. A vehicle control apparatus that performs OWC parallel clutch engagement control to be combined.   The shift control means executes the OWC parallel clutch engagement control when the idle stop request is generated during vehicle deceleration, and then stops the combustion of the engine by the idle stop control means. Item 2. The vehicle control device according to Item 1.   If a restart request is generated during the execution of the OWC parallel clutch engagement control when the vehicle is decelerated due to the combustion stop of the engine, the shift control means restarts the engine after the OWC parallel clutch engagement control ends. The vehicle control device according to claim 1, wherein the vehicle control device is started.   The shift control means gradually increases the hydraulic pressure supplied to the OWC parallel clutch so that the OWC parallel clutch is gradually engaged while slipping during execution of the OWC parallel clutch engagement control. The vehicle control device according to claim 1. Idle stop prediction means for predicting the possibility of occurrence of the idle stop request during vehicle travel,
The shift control means supplies the hydraulic pressure to the standby hydraulic pressure immediately before the OWC parallel clutch is engaged when the possibility of the generation of the idle stop request is predicted by the idle stop prediction means. The vehicle control device according to any one of claims 1 to 4, wherein combined standby control is executed.   The shift control means rapidly fills the OWC parallel clutch with the hydraulic pressure up to the standby hydraulic pressure by setting a hydraulic pressure command value to a hydraulic pressure higher than the standby hydraulic pressure at an early stage of the engagement standby control. The vehicle control device according to claim 5.   The vehicle control device according to claim 5 or 6, wherein the idle stop prediction means predicts the possibility of occurrence of the idle stop request based on at least a vehicle speed.   The vehicle control device according to claim 7, wherein the idle stop prediction unit predicts the possibility of occurrence of the idle stop request based on a vehicle speed and a deceleration.   9. The shift control means according to claim 1, wherein the OWC parallel clutch engaged by the OWC parallel clutch engagement control is released at a predetermined time after the vehicle is stopped or the engine is restarted. The vehicle control device according to any one of the above.   The vehicle control according to claim 9, wherein the shift control means releases the OWC parallel clutch when the OWC parallel clutch starts to transmit torque after the engine is restarted by the idle stop control means. apparatus.   When the engine speed exceeds the turbine rotation speed of a torque converter provided between the output shaft of the engine and the input shaft of the speed change mechanism after the engine is restarted by the idle stop control means. The vehicle control device according to claim 9, wherein the OWC parallel clutch is released.   10. The OWC parallel clutch is released according to claim 9, wherein the speed change control unit releases the OWC parallel clutch when an engine rotation speed of a predetermined value or more continues for a predetermined time or more after the engine is restarted by the idle stop control unit. Vehicle control device.   The speed change control means, when the engine speed exceeds the turbine speed of a torque converter provided between the output shaft of the engine and the input shaft of the speed change mechanism after the engine is restarted by the idle stop control means or 10. The vehicle control device according to claim 9, wherein the OWC parallel clutch is released at an earlier timing from when the engine speed exceeds a predetermined value for a predetermined time or longer.

Images