JP6642472B2 - Vehicle control device - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a vehicle control device capable of executing coasting control for suppressing a brake torque.

  2. Description of the Related Art A control device of a vehicle that executes coasting control for suppressing a brake torque when an execution condition including an accelerator off is satisfied during traveling is well known. For example, this is the coasting control device described in Patent Document 1. According to Patent Document 1, when the accelerator is off and the brake is off and the vehicle speed is equal to or higher than a specific vehicle speed, road conditions such as a road gradient or an intersection ahead in the traveling direction, an inter-vehicle distance to a preceding vehicle detected by a sensor, and the like. It is disclosed to judge whether or not coasting is possible based on this.

JP 2014-50312 A

  By the way, if the condition relating to the preceding vehicle located in the traveling direction of the vehicle is included in the execution condition of the coasting control, the coasting control may not be performed depending on the behavior of the preceding vehicle, and the opportunity of the coasting control is limited.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an opportunity to execute the coasting control when the execution of the coasting control is determined including the condition regarding the preceding vehicle. It is an object of the present invention to provide a control device for a vehicle that can be increased.

The gist of the first invention is (a) a vehicle control device that executes coasting control for suppressing a brake torque when an execution condition including an accelerator off is satisfied during traveling, and The execution condition includes a condition relating to a preceding vehicle positioned in the traveling direction of the vehicle, and (c) a request command requesting the preceding vehicle to perform control such that the condition relating to the preceding vehicle is more easily satisfied. And (d) controlling the vehicle speed by controlling the wheel brakes so that the condition relating to the preceding vehicle is more easily satisfied when transmitting the request command. Is to do.

According to the first aspect, a request command requesting the preceding vehicle to perform control such that the condition relating to the preceding vehicle is more likely to be satisfied is transmitted to the external device . At this time, the condition relating to the preceding vehicle is more likely to be satisfied. as, Runode controlled vehicle speed by controlling the wheel brakes, condition regarding previous row vehicle is easily satisfied. Therefore, when the execution of the coasting control is determined including the condition related to the preceding vehicle, the opportunity to execute the coasting control can be increased.

FIG. 1 is a diagram illustrating a schematic configuration of a drive device provided in a vehicle to which the present invention is applied, and a diagram illustrating a main part of a control function and a control system for various controls in the vehicle. It is a figure for explaining a mode when not performing engine load reduction control, and a mode when performing each of a plurality of types of engine load reduction control. 4 is a flowchart illustrating a control operation for increasing the chances of executing the coasting control when the execution of the coasting control is determined including a main part of the control operation of the electronic control device, that is, a condition relating to a preceding vehicle. 4 is a flowchart illustrating a main part of a control operation of the electronic control device, that is, a control operation for optimizing engine stop control.

  In an embodiment of the present invention, the vehicle includes a power source and a transmission that transmits power from the power source to driving wheels. The power source is, for example, an engine such as a gasoline engine or a diesel engine that generates power by burning fuel, and / or a rotating machine. When the power source is the engine, the brake torque corresponds to an engine brake torque. When the power source is the rotating machine, the brake torque corresponds to a regenerative brake torque. As described above, the brake torque is a brake torque by the power source (power source brake torque), but may be a brake torque by a rotating machine exclusively provided for power generation. That is, the brake torque may be a brake torque of the prime mover (primary motor brake torque). The transmission includes, for example, a known planetary gear type automatic transmission, a known synchronous mesh type parallel two-shaft manual transmission, a known synchronous meshing parallel two-shaft automatic transmission, and a synchronous meshing parallel two-shaft automatic transmission. Examples thereof include a known DCT (Dual Clutch Transmission) of a type having two input shafts and a known belt-type or toroidal-type continuously variable transmission.

  In addition, the vehicle includes a disconnection device in a power transmission path between the power source and the drive wheel, which disconnects power transmission in the power transmission path. The control device suppresses a power source brake torque by disconnecting the power source from the drive wheel by the connection / disconnection device. The connection / disconnection device uses a frictional engagement type clutch or brake. However, various modes such as enabling / disabling power transmission in the power transmission path by electrically controlling a reaction force can be used. Can be adopted. An automatic transmission having a plurality of clutches and brakes and capable of being in a neutral state may be used as the connection / disconnection device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of a drive device 12 provided in a vehicle 10 to which the present invention is applied, and also illustrates a main part of a control system for various controls in the vehicle 10. In FIG. 1, a driving device 12 is connected to an engine 14 as a power source, an automatic transmission 16 directly or indirectly connected to the engine 14 via a damper (not shown), and an output rotating member of the automatic transmission 16. And a pair of axles 20 and the like connected to the differential gear device 18. In the drive unit 12, the power output from the engine 14 (the torque and the force also have the same meaning unless otherwise specified) are transmitted to the automatic transmission 16, and the vehicle is transmitted from the automatic transmission 16 via the differential gear device 18 and the like. The power is transmitted to the drive wheels 22 included in the motor 10.

  The engine 14 includes an engine control device 24 having various devices necessary for controlling the output of the engine 14, such as an electronic throttle device, a fuel injection device, and an ignition device. The engine 14 is controlled by an electronic control unit 50 described later in accordance with an accelerator pedal operation amount (accelerator operation amount) θacc corresponding to a driver's request amount for driving the vehicle 10 by the driver. The torque Te is controlled. For this reason, the throttle opening tap, which is the opening of the throttle valve provided in the electronic throttle device, is also a value corresponding to the required drive amount.

  The automatic transmission 16 is a stepped transmission that forms part of a power transmission path between the engine 14 and the drive wheels 22. The automatic transmission 16 includes, for example, a plurality of sets of planetary gear devices and a plurality of hydraulic frictional engagement devices (hereinafter, referred to as engagement devices CB) such as clutches and brakes. Transmission. Each of the engagement devices CB operates in the engagement state (engagement state) by changing the torque capacity by adjusting each engagement hydraulic pressure output from a solenoid valve or the like in a hydraulic control circuit 26 provided in the vehicle 10. And release). The automatic transmission 16 has a plurality of gear ratios (gear ratios) e (= transmission input rotation speed Ni / transmission output rotation speed No) different from each other due to engagement of a predetermined engagement device among the engagement devices CB. One of the gears (gears) is established. In the automatic transmission 16, an electronic control unit 50 described later controls the operating state of the engagement device CB according to the accelerator operation of the driver, the vehicle speed V, and the like, thereby switching the gear position to be formed (that is, the gear position to be formed). A plurality of gears are selectively formed). Further, the automatic transmission 16 is brought into a neutral state in which no gear stage is formed (that is, a neutral state in which power transmission is cut off) by releasing any of the engagement devices CB. The clutch C1 is one of the engagement devices CB, and functions as an input clutch of the automatic transmission 20. The clutch C1 is provided in a power transmission path between the engine 14 and the drive wheels 22, and connects or disconnects the power transmission path (that is, enables or interrupts power transmission in the power transmission path). ) Functions as a disconnecting device. Accordingly, the automatic transmission 16 is brought into the neutral state by releasing the clutch C1. Note that, as the automatic transmission 16, a known belt-type continuously variable transmission can be used instead of the stepped transmission.

  Further, the vehicle 10 includes a transceiver 28. The transceiver 28 is a device that exists separately from the vehicle 10 and communicates with the center 100 (also referred to as the center 100) as an external device different from the vehicle 10. An electronic control unit 50 described below transmits and receives various information to and from the center 100 via the transceiver 28. The center 100 has a function as a server, and accepts, processes, accumulates, and provides various information. As with the vehicle 10, the center 100 communicates various kinds of information with other vehicles 110a, 110b, 110c, 110d, and 110e (other vehicles 110 unless otherwise distinguished) from the vehicle 10. Send and receive The other vehicle 110 has basically the same function as the vehicle 10.

  In particular, among the other vehicles 110, for example, the other vehicles 110a, 110b, and 110c are preceding vehicles located in the traveling direction of the vehicle 10 (for example, see the vehicle 10 shown by a broken line in FIG. 1). When this preceding vehicle is represented, the other vehicles 110a, 110b, 110c are represented as preceding vehicles 120a, 120b, 120c (hereinafter referred to as the preceding vehicle 120 unless otherwise distinguished). The preceding vehicle 120 is the nearest other vehicle 110 or the other vehicle 110 near the traveling direction of the nearest other vehicle 110 in the traveling direction of the vehicle 10 (not necessarily a straight line), Another vehicle 110 existing within a predetermined distance A that can be detected by a known obstacle sensor or the like, and another vehicle 110 existing within a predetermined distance B that the driver can visually recognize. If the vehicle 10 proceeds as it is, it is assumed that there is another vehicle 110 or the like existing on the traveling path determined to be highly likely to travel.

  Further, the vehicle 10 includes an electronic control device 50 as a controller including a control device of the vehicle 10 related to control of the engine 14, the automatic transmission 16, and the like. The electronic control unit 50 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and operates according to a program stored in the ROM in advance. Various controls of the vehicle 10 are executed by performing signal processing. The electronic control unit 50 is divided into an engine control unit, a shift control unit, and the like as necessary.

  The electronic control unit 50 includes various sensors provided in the vehicle 10 (for example, an engine speed sensor 30, an input speed sensor 32, an output speed sensor 34, an accelerator operation amount sensor 36, a throttle opening sensor 38, a GPS antenna And the like (for example, the engine rotation speed Ne which is the rotation speed of the engine 14, the transmission input rotation speed Ni which is the input rotation speed of the automatic transmission 16, and the vehicle speed V). The transmission output rotation speed No, which is the output rotation speed of the corresponding automatic transmission 16, the accelerator operation amount θacc indicating the magnitude of the driver's acceleration operation, the throttle opening tap, the GPS signal, etc. The position information Svp of the vehicle 10 is supplied. Further, the electronic control unit 50 sends various command signals (for example, an engine control command signal Se for controlling the engine 14) to various devices (for example, the engine control device 24 and the hydraulic control circuit 26) provided in the vehicle 10. A hydraulic control command signal Sp for controlling the operating state of the combined device CB is output. The hydraulic control command signal Sp is, for example, a command signal (drive current) for driving a solenoid valve or the like for adjusting each engagement hydraulic pressure Pcb supplied to each hydraulic actuator of the engagement device CB, and includes a hydraulic control circuit. 26. The electronic control unit 50 sets a hydraulic command value (instruction pressure) corresponding to the value of each engagement hydraulic pressure Pcb supplied to each hydraulic actuator, and outputs a drive current according to the hydraulic command value.

  The electronic control unit 50 includes an engine control unit or engine control unit 52, a shift control unit or shift control unit 54, and a load reduction control unit or load reduction control unit 56 in order to implement various controls in the vehicle 10. .

  The engine control unit 52 controls the engine control device 24 so as to obtain the requested engine torque Te. For example, the engine control unit 52 applies the accelerator operation amount θacc and the vehicle speed V to a relationship (for example, a driving force map) obtained and stored in advance (that is, predetermined) experimentally or in design, A required drive torque Tdem as a required drive amount is calculated. The engine control unit 52 outputs an engine control command signal Se for controlling the engine 14 such that the engine torque Te that achieves the required drive torque Tdem is obtained in consideration of the gear position of the automatic transmission 16. As the required drive amount, in addition to the required drive torque Tdem [Nm] of the drive wheel 22, the required drive force Fdem [N] of the drive wheel 22, the required drive power Pdem [W] of the drive wheel 22, the automatic transmission 16 , The required transmission input torque Tidem of the automatic transmission 16, the required engine torque Tedem of the engine 14, and the like. Further, as the drive request amount, the accelerator operation amount θacc [%], the throttle opening tap [%], the intake air amount of the engine 14 [g / sec], and the like can also be used.

  The shift control unit 54 executes a shift control of the automatic transmission 16. For example, the shift control unit 54 determines the shift of the automatic transmission 16 using a predetermined relationship (for example, a shift map), and automatically switches the gear of the automatic transmission 16 as necessary. A hydraulic control command signal Sp for switching the operating state of the engagement device CB is output to the hydraulic control circuit 26. The shift map described above is a two-dimensional coordinate system in which, for example, the transmission output rotation speed No (the vehicle speed V and the like are also agreed) and the accelerator operation amount θacc (the required drive torque Tdem and the throttle opening tap are also agreed) are variables. Further, the predetermined relationship has a shift line (upshift line and downshift line) for determining the shift of the automatic transmission 16.

  When a predetermined execution condition is satisfied during inertial running (also referred to as coasting) or vehicle stop (also referred to as stopping), which is deceleration running with the accelerator off, the load reduction control unit 56 stops the engine 14 and stops the engine. The engine load reduction control for performing at least one of disconnection of the fourteen drive wheels 22 from the drive wheels 22 is performed. The load reduction control unit 56 disconnects the engine 14 from the driving wheels 22 by cutting off the power transmission in the power transmission path between the engine 14 and the driving wheels 22 by the clutch C1. Specifically, the load reduction control unit 56 outputs a command for performing a fuel cut (also referred to as F / C) for stopping fuel supply to the engine 14 to the engine control unit 52, and stops the operation of the engine 14. . The stop of the engine 14 here is the stop of the operation of the engine 14, and does not always coincide with the stop of the rotation of the engine 14. The stop of the rotation of the engine 14 depends on, for example, whether the engine 14 is separated from the drive wheels 22 in addition to the F / C. The load reduction control unit 56 outputs a command to release the clutch C1 to the shift control unit 54, and disconnects the engine 14 from the drive wheels 22. The predetermined execution condition is, for example, the execution of the engine load reduction control based on the accelerator-off duration, the vehicle speed V, the wheel brake operating force, the steering angle at the steering wheel, the inter-vehicle distance, the necessity of warming up the engine 14, and the like. This is a predetermined condition for determination.

  When the engine 14 is not stopped by the engine load reduction control, the engine 14 is set to, for example, an idling state. Further, the release of the clutch C1 in the engine load reduction control may be a complete release such that the engagement oil pressure of the clutch C1 becomes substantially zero, but in consideration of the responsiveness of starting or acceleration after canceling the engine load reduction control. It is desirable that the clutch C1 be semi-disengaged (engagement standby state) such that a predetermined engagement hydraulic pressure that does not generate torque capacity is supplied to the clutch C1. However, when the engine load reduction control involves stopping the rotation of the engine 14, the mechanical oil pump rotationally driven by the engine 14 cannot generate the operating oil pressure to be supplied to the oil pressure control circuit 26. Therefore, in a vehicle that performs engine load reduction control that simultaneously stops the engine 14 and disengages the clutch C1, it is possible to generate an operating oil pressure to be supplied to the oil pressure control circuit 26 separately from the mechanical oil pump. And an electric oil pump.

  The engine load reduction control includes, for example, idling stop control (also referred to as idle stop control or stop eco-run control), deceleration eco-run control, free-run control, neutral control (also referred to as N control), neutral coasting control (also referred to as N coasting control), or the like. It is. FIG. 2 is a diagram for describing a mode when engine load reduction control is not performed and a mode when each of a plurality of types of engine load reduction control is performed. 2, in the normal control in which the engine load reduction control is not performed, the engine 14 is operated and the clutch C1 is engaged while the vehicle is stopped or running. In the stop eco-run control, the engine 14 is stopped and the clutch C1 is released while the brake is on and the accelerator is off. In the deceleration eco-run control, the engine 14 is stopped and the clutch C1 is disengaged during coasting at a low vehicle speed (that is, during a period from deceleration traveling near stopping to stopping). In the free-run control, the engine 14 is stopped and the clutch C1 is released during coasting at a medium to high speed. In the N control, the engine 14 is operated in an idling state and the clutch C1 is released while the vehicle is stopped. In the N coasting control, during coasting, the engine 14 is operated in an idling state and the clutch C1 is released.

  In the engine load reduction control for disconnecting the engine 14 from the drive wheels 22 during coasting, when the clutch C1 is completely released, no engine brake torque is applied, or when the clutch C1 is brought into a slip engagement state. Engine brake torque is reduced. In the present embodiment, among the engine load reduction controls, the execution conditions including the deceleration eco-run control, the free-run control, and the N-coast control, in which the engine 14 is disconnected from the drive wheels 22 during coasting, including the accelerator-off during traveling are satisfied. This is referred to as coasting control that suppresses the engine brake torque when it is performed.

  By the way, the actual fuel efficiency (also referred to as the actual fuel efficiency) is improved by performing the engine load reduction control. However, depending on the behavior of the preceding vehicle 120, it is necessary to restart or re-accelerate immediately after the execution of the engine load reduction control. Therefore, in the engine load reduction control that involves stopping the engine 14 (for example, the stop eco-run control, the deceleration eco-run control, and the free-run control), the engine stop time is shortened, which may lead to deterioration of fuel efficiency and drivability. On the other hand, it is conceivable to set a predetermined execution condition so that the engine 14 is stopped with a margin in order to cope with the behavior of the preceding vehicle 120. Then, the engine load reduction control can be executed from the vehicle 10 or the road condition, but the execution of the engine load reduction control may be limited in order to cope with the behavior of the preceding vehicle 120.

  In the present embodiment, the fuel efficiency and drivability are improved by exchanging or acquiring information on the operation and state of the vehicle 10, information on the road environment, and information on the operation and state of the preceding vehicle 120 through the center 100. It is proposed to set the execution condition of the engine load reduction control (also referred to as engine stop control) accompanied by the stop of the engine 14 so that the engine 14 is stopped. In other words, by acquiring not only the traveling state of the vehicle 10 that is the host vehicle, but also the operation and control status of the other vehicle 110 from the other vehicle 110 affecting the host vehicle from the shared center 100, the engine stop control is performed. Set the execution conditions appropriately. Therefore, the predetermined execution conditions of the engine stop control include conditions relating to the other vehicle 110 (particularly, the preceding vehicle 120) (for example, the inter-vehicle distance, the behavior of the other vehicle 110 (running situation), the operation situation and control situation of the other vehicle 110) Etc.). The stop area (stop time, stop start vehicle speed, etc.) of the engine 14 is optimized (enlarged / reduced) based on the execution conditions set as described above. At this time, for example, the vehicle speed V, the gear ratio e of the automatic transmission 16, and the wheel brake are controlled so that an appropriate inter-vehicle distance and an engine stop time are obtained.

  In the optimization of the engine stop control, the electronic control unit 50 controls the operation status, the vehicle behavior (driving status) of the preceding vehicle 120 (120a, b, c, etc.) to which the vehicle 10 approaches in the traveling direction, the predicted inter-vehicle distance, and the like. , The engine stop control of the vehicle 10 is changed in real time processing (real time processing). In addition, the electronic control unit 50 stores (records) a history of operations and vehicle behaviors actually performed by the other vehicle 110 in an area (traveling path) where the vehicle 10 is predicted to pass, which is shared (stored) in the center 100. Information is received from the center 100, and engine stop control is performed using the information. Also, in the preceding vehicle 120, the engine stop control is optimized based on the vehicle speed V of the vehicle 10 approaching from behind, the vehicle operation, and the change in the inter-vehicle distance with the vehicle 10. For example, the electronic control unit 50 transmits to the center 100 a request command requesting the preceding vehicle 120 to perform a control included in the execution condition of the engine stop control in the vehicle 10 such that the condition relating to the preceding vehicle 120 is easily satisfied. I do. At this time, the electronic control unit 50 controls the vehicle speed V by controlling the wheel brakes, maintains the optimum inter-vehicle distance, and extends the engine stop time. In addition, the electronic control unit 50 executes control to prepare for the engine stop control based on past traffic congestion information stored in the center 100 and information on uphill and downhill roads based on map information.

  Hereinafter, a control function for optimizing the engine stop control will be specifically described by exemplifying a state in which the free-run control is being executed. The electronic control unit 50 further includes an information processing unit or information processing unit 58, a state determination unit or state determination unit 60, and a control request unit or control request unit 62 to realize this control function.

  The information processing unit 58 includes an operation state of the vehicle 10 (accelerator operation amount θacc, presence / absence of wheel brake operation, etc.), an operation state of the vehicle 10 (throttle opening tap, vehicle speed V, acceleration (deceleration), wheel brake torque, engine). Brake situation, on-board camera information, drive recorder information, pre-collision control information, etc.), execution status of engine load reduction control (engine load reduction control implemented or not implemented, details of engine load reduction control at the time of implementation) The vehicle information Ic is generated by associating such information with the position information Svp of the vehicle 10. The information processing section 58 transfers the vehicle information Ic to the center 100 via the transceiver 28.

  Vehicle information Ic similar to that of vehicle 10 is transferred from another vehicle 110 to center 100. The center 100 stores vehicle information Ic of the vehicle 10 and the other vehicles 110. The center 100 stores map information.

  The information processing unit 58 receives the current vehicle information Ic of the preceding vehicle 120 included in the center 100 from the center 100 via the transceiver 28 as needed after the power of the vehicle 10 is turned on, for example, when the ignition is turned on. I do. The information processing unit 58 also transmits, as necessary, the past vehicle information Ic of the other vehicle 110 associated with the position information Svp of the travel path on which the vehicle 10 is predicted to pass, which the center 100 has, to the transceiver 28. Via the center 100.

  The state determination unit 60 determines whether the stop of the engine is not executable. For example, the state determination unit 60 determines whether or not the vehicle 10 approaches an uphill road based on the map information of the center 100 (or the vehicle 10). Since there is a high possibility that the accelerator is turned on (acceleration operation) on an uphill road, the state determination unit 60 determines that the engine cannot be stopped when it is determined that the vehicle 10 approaches the uphill road. . Alternatively, the state determination unit 60 determines whether or not the preceding vehicle 120 has performed an acceleration operation on a traveling path on which the vehicle 10 is predicted to pass. Since it is predicted that the vehicle 10 will also perform the acceleration operation on the traveling road on which the preceding vehicle 120 has performed the acceleration operation, the state determination unit 60 will stop the engine if it determines that the preceding vehicle 120 has performed the acceleration operation. It is determined that execution is not possible. Alternatively, the state determination unit 60 determines whether or not the preceding vehicle 120 has performed an acceleration operation on a traveling path on which the vehicle 10 is predicted to pass. Since it is predicted that the vehicle 10 will also perform the acceleration operation on the traveling road on which the preceding vehicle 120 has performed the acceleration operation, the state determination unit 60 will stop the engine if it determines that the preceding vehicle 120 has performed the acceleration operation. It is determined that execution is not possible. Here, it may be determined whether or not the other vehicle 110 has performed an acceleration operation on a traveling path on which the vehicle 10 is predicted to pass in the past.

  When the state determination unit 60 determines that the engine cannot be stopped, the load reduction control unit 56 performs preparations for engine restart. Such an embodiment is useful, for example, when the vehicle 10 and the preceding vehicle 120 have a certain distance, but the vehicle 10 approaches the traveling path on which the preceding vehicle 120 has traveled. In such a case, the electronic control unit 50 obtains the vehicle speed V and the operation status of the preceding vehicle 120 on the traveling road, and stops the engine 14 in advance or determines that the engine should be started earlier. More specifically, when there is an uphill road and the preceding vehicle 120 is performing an acceleration operation, preparation for engine restart is executed. Alternatively, when there is a downhill road and the preceding vehicle 120 is performing a wheel brake operation, a preparation for engaging the clutch C1 is performed to use the engine brake.

  The state determination unit 60 determines whether or not the engine stop region can be expanded beyond a predetermined execution condition of the free-run control. For example, the state determination unit 60 determines whether or not the vehicle 10 is in a situation in which it is determined that the vehicle 10 can travel in a steady state. When the preceding vehicle 120 is cruising at a certain vehicle speed V1, the vehicle 10 can run in a steady state at the vehicle speed V1. In this case, the load reduction control unit 56 continues to stop the engine even if the vehicle speed V2 higher than the vehicle speed V1 is a predetermined execution condition. That is, the engine stop region is expanded beyond the predetermined execution condition of the free-run control. When the state determination unit 60 determines that the vehicle 10 is in a state where it is determined that the vehicle 10 can travel in a steady state, the state determination unit 60 determines that the engine stop area can be expanded more than the predetermined execution condition of the free-run control. Alternatively, the state determination unit 60 determines whether or not the vehicle 10 is decelerating from steady running, such as a short inter-vehicle distance with the preceding vehicle 120 (particularly, the closest preceding vehicle 120a). In a situation where the vehicle decelerates from steady running, it is considered that the necessity of the acceleration operation is low. In this case, the load reduction control unit 56 continues to stop the engine until the low vehicle speed range, and shifts to the deceleration eco-run control as it is. That is, the engine stop region is expanded beyond the predetermined execution condition of the free-run control. When the state determination unit 60 determines that the vehicle 10 is decelerating from the steady running, the state determination unit 60 determines that the engine stop region can be expanded more than the predetermined execution condition of the free-run control.

  The embodiment as described above is useful, for example, when the vehicle 10 is considered to catch up with the preceding vehicle 120. In such a case, the vehicle 10 is estimated to have a low vehicle speed V due to running resistance or wheel brake operation from the current state, so the electronic control unit 50 determines that the necessity of restarting the engine is low. More specifically, when the vehicle 10 catches up with the preceding vehicle 120, the engine stop area is continued even at a low vehicle speed or the like by expanding the execution region (vehicle speed condition, etc.) of the free-run control beyond a predetermined execution condition. Then, the engine stop time is extended, and the process directly shifts to the deceleration eco-run control. Alternatively, when the vehicle 10 catches up with the preceding vehicle 120, the engine is not restarted even at the time of a wheel brake operation that releases the free-run control under the predetermined execution conditions of the free-run control, so that the preceding vehicle 120 cruises. The vehicle is decelerated to the vehicle speed V by a wheel brake operation or the like, and the engine is stopped until the inter-vehicle distance with the preceding vehicle 120 is reduced.

  During execution of the free-run control, the control request unit 62 transmits to the center 100 a request command requesting the preceding vehicle 120 to perform a control such that a condition regarding the preceding vehicle 120 is easily satisfied. The condition relating to the preceding vehicle 120 is, for example, whether or not the inter-vehicle distance to the preceding vehicle 120 is equal to or more than a predetermined distance C which is predetermined as a lower limit inter-vehicle distance suitable for executing the free-run control. The request command under such conditions is, for example, a request for prompting an acceleration operation, a request for prompting coasting of the vehicle, a request for prompting cruising of the vehicle, and the like. When the request command is transmitted from the vehicle 10, the center 100 transfers the request command to the preceding vehicle 120. The preceding vehicle 120 to which the request command is transmitted is preferably a preceding vehicle 120 that has been paired with the vehicle 10 in advance, or a preceding vehicle 120 that has been grouped in advance including the vehicle 10. Therefore, the information processing unit 58 transmits a request for pairing or grouping to the preceding vehicle 120 via the center 100 (or directly), or transmits a request for pairing or grouping from the preceding vehicle 120. The data is received via the center 100 (or directly), and upon mutual permission, pairing or grouping is completed. The state determination unit 60 determines whether or not the vehicle 10 and the preceding vehicle 120 are traveling by performing pairing with the preceding and following vehicles, or performs grouping with the plurality of vehicles including the vehicle 10 in the vehicle 10 and the preceding vehicle 120. It is determined whether or not the vehicle is running.

  FIG. 3 illustrates a main part of the control operation of the electronic control device 50, that is, a control operation for increasing the chances of executing the coasting control when the execution of the coasting control is determined including the condition regarding the preceding vehicle 120. It is a flowchart, for example, is repeatedly performed during execution of free-run control. FIG. 3 is also a flowchart illustrating a control operation for optimizing the engine stop control.

  In FIG. 3, first, at step (hereinafter, step is omitted) SA10 corresponding to the function of the state determination unit 60, it is determined whether or not the vehicle 10 and the preceding vehicle 120 are paired with each other before and after the vehicle to travel. Alternatively, it is determined whether or not the vehicle 10 and the preceding vehicle 120 are traveling by grouping a plurality of vehicles including the vehicle 10. If the determination in SA10 is affirmative, in SA20 corresponding to the function of the control request unit 62, control is performed so that the condition relating to the preceding vehicle 120 is easily satisfied. A request command requesting the preceding vehicle 120 that is grouped in advance including the vehicle 120 or the vehicle 10 is transmitted to the center 100, and is transmitted from the center 100 to the preceding vehicle 120. If the determination in SA10 is denied, or, after SA20, in SA30 corresponding to the function of the information processing unit 58, the current vehicle information Ic of the preceding vehicle 120 is replaced with the vehicle information, if necessary. The past vehicle information Ic of the other vehicle 110 associated with the position information Svp of the traveling road on which the passage of 10 is predicted is received from the center 100 via the transceiver 28. Next, in SA 40 corresponding to the function of the state determination unit 60, the current execution condition of the free-run control is compared with a predetermined execution condition, and it is confirmed whether the engine stop region is reduced or enlarged. Next, in SA50 corresponding to the function of the state determination unit 60, it is determined whether or not the engine cannot be stopped. If the determination in SA50 is affirmative, this routine is ended. If the determination in SA50 is negative, in SA60 corresponding to the function of the state determination unit 60, it is determined whether or not the engine stop region can be expanded beyond the predetermined execution condition of the free-run control. If the determination in SA60 is affirmative, in SA70 corresponding to the function of the load reduction control unit 56, the execution area of the free-run control is expanded (that is, the engine stop area is expanded beyond a predetermined execution condition). If the determination in SA60 is negative, in SA80 corresponding to the function of the load reduction control unit 56, the free-run control is performed under predetermined execution conditions. Following SA70 or following SA80, free run control is executed (continued) at SA90 corresponding to the function of the load reduction control unit 56.

  As described above, according to the present embodiment, a request command requesting the preceding vehicle 120 to perform control such that the condition relating to the preceding vehicle 120 is more likely to be satisfied is transmitted to the center 100. When the control is performed by the vehicle 120, the condition regarding the preceding vehicle 120 is more likely to be satisfied. Therefore, when the execution of the coasting control (free-run control) is determined including the condition regarding the preceding vehicle 120, the opportunity to execute the coasting control can be increased.

  Further, according to the present embodiment, since the engine stop control optimal for the road environment and the traffic environment is executed, unnecessary engine stop can be avoided, and the fuel efficiency deteriorates due to the engine restart in a short time after the engine stop, Deterioration of drivability such as acceleration response delay due to engine restart after engine stop, and deterioration of vibration and noise due to engine stop and engine restart in a short time can be avoided or suppressed.

  Further, according to the present embodiment, the engine can be stopped in a wider area (time, vehicle speed V, etc.), the influence on drivability is suppressed, and further improvement in fuel efficiency can be achieved.

  Next, another embodiment of the present invention will be described. In the following description, portions common to the embodiments are denoted by the same reference numerals, and description thereof is omitted.

  In the present embodiment, the engine stop control is optimized by exemplifying a state before execution of stop eco-run control and deceleration eco-run control (hereinafter referred to as eco-run control unless otherwise distinguished), which are engine stop controls different from free-run control. The control function will be specifically described.

  The state determination unit 60 determines whether or not the stopped preceding vehicle 120 has performed a start operation (brake off, accelerator on, and the like). When the preceding vehicle 120 performs the start operation, it is preferable to prepare for re-acceleration or restart without executing engine stop even if the predetermined execution condition of the eco-run control is satisfied. Therefore, when it is determined that the stopped preceding vehicle 120 has performed the start operation, the state determination unit 60 determines that the engine cannot be stopped. Alternatively, the state determination unit 60 predicts the start of the stopped preceding vehicle 120 based on signal switching in front of the preceding vehicle 120, information on the road traffic information communication system, information on the onboard camera, information on the drive recorder, and the like. It is determined whether or not the road environment is correct. In a road environment in which the start of the preceding vehicle 120 is predicted, the engine restart and restart after a short engine stop are predicted. Therefore, the engine stop is not performed, and the predicted re-acceleration or It is preferable to prepare for a restart. Therefore, when the state determination unit 60 determines that the road environment is such that the start of the stopped preceding vehicle 120 is predicted to be stopped, the state determination unit 60 determines that the engine cannot be stopped. Here, the preceding vehicle 120 includes not only the closest preceding vehicle 120a but also the preceding vehicle 120b ahead of the preceding vehicle 120a, the leading vehicle 120c at the head of the stopped preceding vehicle group 120 (120a, b, c), and the like. The subject.

  When the state determination unit 60 determines that the engine cannot be stopped, the load reduction control unit 56 satisfies predetermined execution conditions of the deceleration eco-run control (for example, accelerator off, vehicle speed V is equal to or less than vehicle speed V3). Do not stop the engine even if Alternatively, when the state determination unit 60 determines that the engine stop cannot be executed, the load reduction control unit 56 stops the vehicle 10 and performs predetermined execution conditions of the stop eco-run control (for example, accelerator off, brake on). Do not stop the engine even if

  The state determination unit 60 determines whether or not the engine stop area can be expanded under predetermined execution conditions of the deceleration eco-run control. For example, based on whether the inter-vehicle distance between the vehicle 10 and the preceding vehicle 120 is equal to or greater than a predetermined distance D, the state determination unit 60 determines whether the engine stop area can be expanded beyond a predetermined execution condition of the deceleration eco-run control. Is determined. Further, the state determination unit 60 determines whether the vehicle 10 is in the engine stop region based on whether the vehicle 10 is in the coasting state of the accelerator off and is performing the deceleration operation (such as the brake on), based on the predetermined execution condition of the deceleration eco-run control. It is determined whether or not can be expanded. Further, the state determination unit 60 determines whether the preceding vehicle 120 stops for a predetermined time or more (that is, the continuation of the stop of the preceding vehicle 120 is predicted). It is determined whether the engine stop area can be expanded.

  When the state determination unit 60 determines that the engine stop region can be expanded more than the predetermined execution condition of the deceleration eco-run control, the load reduction control unit 56 sets the engine stop region more than the predetermined execution condition of the deceleration eco-run control. It is expanded (that is, the execution area of the deceleration eco-run control is expanded beyond a predetermined execution condition). The load reduction control unit 56 reduces, for example, the vehicle speed condition that the vehicle speed V is equal to or less than the vehicle speed V3 among the predetermined execution conditions to the vehicle speed condition that the vehicle speed V is equal to or less than the vehicle speed V4 (> V3). As the vehicle speed V4, for example, a different value may be used according to the inter-vehicle distance between the vehicle 10 and the preceding vehicle 120. By relaxing the vehicle speed condition, the engine stop time from deceleration to stop of the vehicle 10 can be extended.

  FIG. 4 is a flowchart for explaining a main part of the control operation of the electronic control unit 50, that is, a control operation for optimizing the engine stop control. For example, when the accelerator is off, the control operation is repeatedly executed before the execution of the eco-run control. You.

  4, first, at SB10 corresponding to the function of the information processing unit 58, current vehicle information Ic of the preceding vehicle 120 is received from the center 100 via the transceiver 28 as necessary. Next, at SB20 corresponding to the function of the state determination unit 60, the current execution condition of the eco-run control is compared with a predetermined execution condition, and it is confirmed whether the engine stop area is reduced or enlarged. Next, in SB30 corresponding to the function of the state determination unit 60, it is determined whether or not the engine cannot be stopped. If the determination in SB30 is affirmative, this routine is ended. If the determination in SB30 is negative, in SB40 corresponding to the function of the state determination unit 60, it is determined whether or not the engine stop region can be expanded beyond the predetermined execution condition of the deceleration eco-run control. If the determination in SB40 is affirmative, the execution region of the deceleration eco-run control is expanded in SB50 corresponding to the function of the load reduction control unit 56 (that is, the engine stop region is expanded more than the predetermined execution condition of the deceleration eco-run control). Is done). If the determination in SB40 is negative, in SB60 corresponding to the function of the load reduction control unit 56, the deceleration eco-run control is performed under predetermined execution conditions. Subsequent to SB50 or SB60, in SB70 corresponding to the function of the load reduction control unit 56, it is determined whether or not the execution condition of the eco-run control is satisfied. If the determination at SB70 is negative, this routine is terminated. If the determination in SB70 is affirmative, the eco-run control is executed in SB80 corresponding to the function of the load reduction control unit 56.

  As described above, according to the present embodiment, the engine stop control optimal for the road environment and the traffic environment is executed, so that unnecessary engine stop can be avoided, and the engine can be restarted in a short time after the engine stop. Deterioration of drivability such as deterioration of fuel efficiency, delay of acceleration response due to restart of the engine after stopping the engine, and deterioration of vibration and noise caused by stopping the engine in a short time and restarting the engine can be avoided or suppressed.

  Further, according to the present embodiment, the engine can be stopped in a wider area (time, vehicle speed V, etc.), the influence on drivability is suppressed, and further improvement in fuel efficiency can be achieved.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention is applicable to other aspects.

  For example, in the above-described embodiment, during execution of the free-run control, a request command for requesting the preceding vehicle 120 to perform a control such that the condition regarding the preceding vehicle 120 is easily satisfied is transmitted to the center 100. Not limited to For example, the request command may be transmitted to the center 100 before the execution of the free-run control such that the free-run control may be executed during the coasting of the accelerator-off. Alternatively, the request command may be transmitted directly to the preceding vehicle 120 without passing through the center 100 by vehicle communication, or the vehicle information Ic may be directly exchanged with the preceding vehicle 120 by vehicle communication. Is also good. In this case, the external device other than the vehicle 10 includes the other vehicle 110 (particularly, the preceding vehicle 120) in addition to the center 100. The transceiver 68 is also a device that communicates with another vehicle 110. Such a mode is useful, for example, when communication between the vehicle 10 and the center 100 cannot be performed for some reason. Alternatively, the coasting control to which the request command is transmitted may be deceleration eco-run control or N coasting control without stopping the engine 14 in addition to the free-run control. Therefore, even if the vehicle 10 is capable of performing only one coasting control among a plurality of types of engine load reduction control of the idle stop control, the deceleration eco-run control, the free-run control, the N control, and the N coasting control, for example. The present invention can be applied.

  Further, in the above-described embodiment, the embodiment in which the request command is transmitted to the center 100 has been described with reference to the flowchart in FIG. 3, but the present invention is not limited to this embodiment. For example, if only the embodiment of transmitting the request command to the center 100 is executed, the control operation related to changing the predetermined execution condition of the free-run control is not necessary in the flowchart of FIG.

  Further, in the above-described embodiment, what is performed in the vehicle 10 and what is performed in the center 100 is performed in any one of the vehicle 10 and the center 100, except that only one of the vehicle 10 and the center 100 can be performed. May be.

  In the above-described embodiment, the preceding vehicle 120 may be an automatic driving vehicle.

  Further, in the above-described embodiment, the clutch C <b> 1 constituting a part of the automatic transmission 16 is illustrated as an example of the connecting / disconnecting device that disconnects the engine 14 and the driving wheel 22. For example, the clutch C1 may be provided independently of the automatic transmission 16. When the automatic transmission 16 is, for example, a belt-type continuously variable transmission, the clutch C1 is provided independently of the continuously variable transmission. The engagement device included in the known forward / reverse switching device may be used as a disconnection device.

  It should be noted that the above is merely an embodiment, and that the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

10: Vehicle 50: Electronic control device (control device)
100: Center (external equipment)
120: preceding vehicle

Claims (1)

A control device for a vehicle, which performs coasting control for suppressing a brake torque when an execution condition including an accelerator off is satisfied during traveling,
The execution condition includes a condition relating to a preceding vehicle located in a traveling direction of the vehicle,
A request command for requesting the preceding vehicle to perform control such that the condition relating to the preceding vehicle is easily satisfied is transmitted to an external device different from the vehicle ,
When transmitting the request command, a vehicle control device controls a vehicle speed by controlling a wheel brake so that a condition relating to the preceding vehicle is easily satisfied .

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